I know this may be difficult but I think you should strictly focus on your own mental health. We can’t change people, your mom is on her own path. You should seek a therapist and psychiatrist if you have insurance and pursue and healthier lifestyle. I’m speaking from experience, I was diagnosed one year ago. Prior to my diagnosis I acted in very risky behavior (a lot of drugs and sex) and then bouts of a deep suicidal depression. Once i began therapy and learned about DBT and found meds that work for me my quality of life truly improved. I think you should talk to your mom and her son and try to see if they’re open to therapy as well but if they’re not you should do it for yourself. You owe it to you :)<3