tl;dr - It really is a friend, not me. I don't have much experience with the issue and can't find adequate resources for help.

My friend is a middle-aged female (45-50) who cuts her legs and stomach. She hates herself, hates her body, and has a poor self-image. I find her more attractive than girls half her age, so it's hard for me to understand as a guy why she feels that way.

She's been to therapy and found it useless, so she refuses to ever go again. She doesn't do drugs, but she is a functional alcoholic.

I try to get her to talk about why she cuts herself, but she stonewalls me with "I don't know" every time.
It's my opinion that she does know, but doesn't want to tell me. She doesn't tell anyone about her cutting, but she will at least confide in me that she's done it. This last time was really bad and she asked me for advice on how to treat it medically since I have some basic knowledge on the subject.
There are only so many reasons to do it, right? I've read that some people like the rush they get from cutting. Others do it because they hate what they see. Some want attention.
I really don't know. She hides it from everyone, so I don't believe it's for the attention. She definitely hates herself, but for no good reason. She's incredible in my eyes. She doesn't deserve the hand she was dealt in life and I wish I could save her, but I know I can't. She's said exactly as much to me already, but that's not going to deter me from ever trying to help her.

This is why I'm reaching out to the community here. If there's anything you can tell me about how I can best help her, please let me know. Direct me to the best resources. Something. Anything.
Thank you all in advance, with love.