Remember, there are a lot of people who go through the same mental tortures as you do. Some even for the entire lifetime. I'm one of them. I feel it can help to find and create a safe space for yourself and try to find someone who goes through the same troubles as you do and open up, even if it won't fix the torture it can create a bond, it can uplift you and strengthen you. Yes I'm being a hypocrite as I'm not even strong enough for my own advice lol. Also, based on this little post, it seems like you love this game a lot but it also puts a lot of strain on you. My rule is, if a game puts this much strain on my mental health, which is already in shambles, I look for something else. I never play vs people or in parties as you mentioned there are very toxic people out there and PvP is a game you cannot win, especially for people suffering from depression. You feel even worse and you start to bash yourself even more. Don't be ashamed or afraid to look for someone else that understands you, goes through severe depression and that will help you more than anything else.

I can speak from my own personal experience. My issue is that I have suffered as a child from physical abuse, my mom got abused plenty of times in front of me 24/7 and it has caused PTSD accompanied with severe depression. What happens is you feed off pain and you torture yourself more than anyone else, it's like digging a hole and the more you think the deeper that hole becomes. Whenever people come close you shut everyone off. You feel like you aren't worthy. And you're afraid of everything.

Counceling can work for some, it didn't work for me.