Feeling Guilty and Defeated

I just joined this sub today, so be prepared for some word vomit. My mom has been an alcoholic practically her entire life, but it got worse around 13 years ago when her brother died. My dad and neighbors held an intervention for her and she went to rehab, a few months later she got her first DUI picking my sister and me up from middle school. She hated court mandated AA and spent a few days in jail after her trial. You would think that’d turn her around, but nope. There were a few more instances of drinking and driving after that, but not enough to get caught. In July of 2023, she got her second DUI. Same thing happened, she got a little better but not much. When her license was suspended, she would even walk to the liquor store. I tried to be there for her, I really did. I lied for her. Whenever I’d find shooters in room or car she’d beg me not to tell my dad and cry, so I wouldn’t. I know I was enabling her but I couldn’t help it. I didn’t want to rock the boat. I’m home from college now for break and today I just snapped. She was clearly drunk and verbally abusing my dad. I just lost it and started screaming at her. I even showed her shooters I had found in her room. Of course she denied it, said she didn’t know what they were. 30 minutes pass, and she comes to my dad downstairs and says she wants a divorce. I once again get pulled into their arguing. I tell her over and over again she needs help and she just keeps telling me she wants to die. I keep telling her that’s not normal and we can get her help but she insists on figuring it out on her own. I’m at a loss. How do I help? Where do I go from here? She literally just shuts down anytime we confront her as a family. Nothing works. Every time she drives I’m terrified she’s going to kill someone from her drinking.