I'm sorry to hear that. I know what its like to have done permanent or long lasting damage to your self with drugs. You have so much regret. i would reccomend books like Hardwiring happiness, mindful guide to self compassion, and resilient.
i'm sorry i can give some reccomendation of how to actually stop your issue. We need to just move on and try to enjoy whatever positive things we do have in our life. We have to remember that EVERYONE, and every animal suffers. we all suffer in life at some point. life is suffering its as much a part of life as shitting. we need to just try and accept that as best we can and focus on the positive.
i know it sound like a lot of bullshit...but its really the only thing you can do to deal with suffering.