Putting down a cat...(very heavy, serious question)

I live in my parent's house while they are in the Middle East. With that house comes two cats, one of which is 17 or 18 years old. As I see it, looking after those cats is the least that I can do in exchange for the support that they are giving me.
 
But you can probably tell form the title that all is not right here. That old cat is, well old. She is slow, I believe deaf, has thyroid issues...and not longer seems able to use the litter box. Every day that I come home from my long commute to the city I find a few places where she has "done the buissness" and I have to take care of it. I recently brought her in to the vet and found out that she had an infection which cost us over 200 dollars to deal with. With all of this in mind I am deeply conflicted. On the one hand, this is an old cat and she is probably not long for this world anyway. I no longer feel that I can have people over due to the embarrassment of having a house that can sometimes be quite nasty (not that I tend to have much company as it is). I also don't like feeling that my own home is so far out of my control.
 
On the other hand, this is a responsibility which is pretty small compared to what my parents are doing for me, so I don't feel that I have much right to take part in the decision about whether to put her down or not. She doesn't SEEM to be suffering at all, though she does seem tired and sluggish. Ultimately, this is the kind of decision that I tend to avoid when possible, and one of the reasons that I personally never want my own pets.
 
Now my parents know about the issues that she has been having and its quite possible (and even likely)  that they are going to make a call in the next few days, but I'm not really sure if I should be taking a stand on the issue or waiting for them to deal with it. I'm really tired of picking up crap, but I'm pretty sure that they are tired of paying for me to go to university. And I don't really want to be responsible for this situation.
 
Does anybody have any advice for me in this situation? I am feeling rather lost.
 
EDIT: There seems to be come confusion, so to clarify: I'm not going to put down my mom's cat until she tells me to. I'm just wondering if I should even be part of the decision. If it actually came down to me, I would never put down the cat because I don't think I could be responsible for killing anything more significant than a fly. I should also clarify that this non-litterbox use may or may not be part of larger medical issues...

I'd wait for them to make the call. I don't know what the $200 process will do for the cat, but I would hold off until your parents contact you.

I was expecting "my cat has cancer, what do". However, if your cat is just an "inconvinience" nut the fuck up and take care of it. Being a cat person myself, I don't think you have the right to put down the cat just because it shits everywhere. 
 
I can't tell if you yourself love these cats, but assuming you parents have owned them for a decade and a half and love them very much, you'd be a dipshit to take on the responsibility to put them down.

Give them away?

So basically, you're thinking of killing you're cat while your parents are away? You say it doesn't seem to be suffering, so putting it down would just mean ending it's life prematurely.

The only times I put down an animal was because they had cancer. One time it was my cat that wouldn't eat and tried running away several times. The other time was my dog who had serious cancer and the operation had something like a 40% chance to survive for 6 months if it was a success.

It sounds like the cats issues are not dire enough, that you need to make a decision until they get back. I had a 21 year old cat, and that thing was a pain, crawling into every hard to get to place to crap, i think it was going insane from old age, eventually it just disappeared one day while it was outside.

Firstly, if this was my cat and there was no suffering involved I wouldn't for a second be considering putting it down just because it can be an inconvenience at times.  Secondly, I believe it is up to your parents and the vet what is best for the cat.

I see, I'll delete the post.

I had to put down my 5 year old cat because it had Leukemia and a stomach condition where it couldn't even ingest water without throwing it back up. That was hard 
 
I don't think this compares at all but do what you must. I personally find it kinda funny

Human comfort>Animal existence

" Human comfort>Animal existence "

" @Zimbo:@EVO: Please refer to edit in OP. "

" EDIT: There seems to be come confusion, so to clarify: I'm not going to put down my mom's cat until she tells me to. I'm just wondering if I should even be part of the decision. If it actually came down to me, I would never put down the cat because I don't think I could be responsible for killing anything more significant than a fly. I should also clarify that this non-litterbox use may or may not be part of larger medical issues... "

As many people have said, it is not your discussion so all you can do is report what is going on.  Honestly if you can afford to start treatment, then the cat would probably have a better quality of life.
 
Now I am going to relate a story about a cat own that had a 24 year old cat that was just skin an bones, and it took all sorts of meds.  I personally would have put that cat down, because he had a bad quality of life.  I mean when you are injecting 3 types of pain meds into your cat everyday so it will eat, and then force feeding it half the time there is something VERY wrong.
 
Now if it is a local infection, like a bladder infection, then I think it is defiantly worth it to treat the cat if it still eats and perks up after a few days of treatment.  The big thing now is that the cat is suffering, so something needs to be done for it.

" @EVO: Thanks, Very helpful. In think that I gave up the possiblity of getting into girl's pants when I put up the 15th video game poster in my room.-_- "

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Yeah I mean when it comes down it, it's your parents' decision. However, you know what her day to day life is like, so I think you can offer your opinion. If the $200 fee for fixing the infection from the vet will substantially improve the cat's life, then you can offer your support for that. If not, and if she has other problems that are only going to get worse, I would recommend having the cat put down. She is the one who has the worst deal, your job right now is to make her feel better. If the peeing everywhere is a really big issue for you, try closing her off in a smaller room or area for when you leave. The cat can't help being sick.
 
Whether you want to or not, you come off sounding pretty callous in your post. This cat is an embarrassing inconvenience in your mind, when really you should be thinking about what is best for the cat, and only what is best for the cat. Sometimes, having an animal euthanized is the best option, but only the vet can tell you whether it is or not.

" Human comfort>Animal existence "

Talked to my wife about this. Did the vet give you the option of putting the cat down? The Vet may only allow you to treat the infection, there would be no choice to put the cat to sleep as a form of resolving the problem. The pet needs to be in severe pain that putting it to sleep would be better than the it was going through. You can't walk into a pet hospital and ask to have it put to sleep because "It's old."
 
A pet is your parents responsibility and have to take care of it as if it was a child. They need to try their best to pay for the medical needs of the cat, try to treat it at home the best they can or choose to surrender it. Sad part is, surrendering it to a shelter probably means that is where the cat will live out the rest of their days. 
 
It is difficult as we are dealing with the same problem with our cat. We love the damn thing but it is expensive with her current medical problem. 

I would just like to say that I am extremely dense and I thought the topic title referred to literally putting down a cat you were carrying, and it was too heavy to put down safely.
 
Anyway, I hate cats for the most part, but if it's your parents' I think you should just live with it until they come back, unless both a vet and your parents give you permission to do otherwise. If they tell you they'll reimburse you for treating its infection (I assume they should since you say they love it dearly), then there's nothing really that egregious about living with it. I mean, I don't like their company that much and I know it's probably shitting in some weird places, but I don't think it's that bad.

I admit, when I read this, it sounded like you just wanted to put the animal down so you didn't have to deal with the poop, instead of wanting to put it down because it's suffering.
 
As someone stated before, try either putting the cat away when you leave. Also, a question, how many litter boxes do you have in your home? It might not even be an issue about the feline being old, it's just that it dosen't want to share space with the other cat any longer. I have two cats myself and currently 3 litterboxes in my home. My older female preference's is an open box, while my smaller female likes closed boxes one for urin and the other for poop.
 
I do this because one box just wasn't enough, and they started trying to go in other places, which i thought odd, it turned out they didn't want to share that much space together. Thus now 3 boxes.
 
Try it and see how it works, it may be just the need for someplace new to go.

What @Catolf: said. 
 
With the two cats we have in the house, we have two boxes in the house. Our older one is very paranoid so we have a covered one in the washroom which she will use when needed but we have another one they both share. It could be worth trying to add an additional liter box.

I'd wait for your parents to give you a verdict. The cat is theirs after all.

i think it's the time to put the cat away. you should call your parents and tell them.

XD

If you don't believe in killing, well i'm sorry you gotta mop up cat piss.
If I were you though, i'd get him put the fuck down. No reason a cat should make it to 17 or 18 anyway.

" If you don't believe in killing, well i'm sorry you gotta mop up cat piss. If I were you though, i'd get him put the fuck down. No reason a cat should make it to 17 or 18 anyway. "

Having recently just put down my dog, which was in the same situation as the cat with a really bad, infected tumour on its back, we only put it down once it became clear the tumour was bothering her (as in she was constantly whining, and trying to lick it, but couldn't, which drove her insane). As long as the cat seems happy, it could be blind, deaf and have a cough, but as long as it's happy, no need to put it down.
 
On whether or not you should be part of the decision, it depends how long you've looked after the cat, and whether or not these issues have developed while your parents have been away.

" @regularassmilk said:

" If you don't believe in killing, well i'm sorry you gotta mop up cat piss. If I were you though, i'd get him put the fuck down. No reason a cat should make it to 17 or 18 anyway. "

cats that live in doors can lead lives up to 25 years of age. Unlike outdoor cats that may only lead less then, or half that. I guess I'm glad your not him. "

" @Catolf said:

" @regularassmilk said:

" If you don't believe in killing, well i'm sorry you gotta mop up cat piss. If I were you though, i'd get him put the fuck down. No reason a cat should make it to 17 or 18 anyway. "

cats that live in doors can lead lives up to 25 years of age. Unlike outdoor cats that may only lead less then, or half that. I guess I'm glad your not him. "

I read multiple times that the average US housecat lives from 12-14 tops. My Great Grandma lived until she was 107. Possible? Yes. Common? No. And the last 20 years of her life were bullshit miserable.  "