If someone thinks you're a "pussy" for refusing to follow their exercise regimen then they are utterly insane. I have permanent nerve damage on the right side of my body and fibromyalgia, my gym regimen consists of me going into the gym in a wife beater, looking swole, and then proceeding to lift with low weight and low reps because it's agonizing.
There's no way in hell everything works for everyone, the bottom line is, do what's safe for you, and do whatever is going to keep you fit and healthy. Otherwise, stick a fork up your ass. You can overtrain if you like, and if anyone tells you to do otherwise, you can tell them to go stuff themselves, but at the same time, you are likely doing something retarded.