I wish you all the luck in the world. Dota 2 seems way harder than League from the 2 or 3 games I played of it. The furthest I got in League was Silver 2. Seems to me that you are burned out on playing these games seriously or Ranked. If thats the case you could play other games or other Mobas and play casualy. If you are in it to have fun, just have fun. I hate myself as well when I keep losing in LoL but there I go again. Whats important is to take a break. It also happens in other hard games. You bang your head against a wall all day, you leave and come back later and it turns out you succeed in the first try.
Heres a plan I have implemented if you really can't stop playing League or Dota it works the same: Everyday just play best 2 out of 3. If you win 2 games in row, there you made your daily League quota, now play Normals or some other game there are so many out there. Somedays I actually just play 1 game a day. Win or lose I just accept it and move on.
Our situations might be different, I am married and I don't have that much time and playing too much was certainly creating problems with the wife. So you can go ahead and use my plan to cool things with League and not burn out on what is a really cool game.