Hey
I can understand how you feel. Sometimes I get so frustrated with trying to make myself feel better, and it can seem completely hopeless, and like nothing will ever change no matter how hard I try. It's not easy to feel depressed, and it's not easy to have to keep fighting to make yourself feel better either. It really gets tiring.
I'm not sure what advice I can offer, but I just want to say I can understand. You're not alone in your fight. I think you need to have some kind of motivation, something you look at and say "I'm going to get better for this."
For me it's my future, my career. I want to be a writer. I want to be happy. Everytime I go to see my psychiatrist or therapist and really don't want to talk I think "I will be thankful for this in ten years." And it really does help.
So find that thing that keeps you fighting, everyone has something they're willing to fight for. It might really help you.