Don`t want to socialize at all

I have avoidant personality disorder, BPD and moderate depression. I don't want to socialize with other people at all, I don't want to meet friends (even if they want to meet me) I don't want to meet new people. I fear of going to school and meeting classmates there, Im so lucky that its summer break. I only sometimes talk to my mother. I even avoid my psychiatrist I have a huge fear of socializing and I don t know how to deal with it.
I used to be a professional swimmer but I quit because of fear of failing, depression and anxiety.
Does anyone have any tips on what I can do?

You could talk to a sports psychologist.