How can I help?

I don’t know how to help my friend.
Her partner has a drug and gambling addiction. It has gotten so bad that he owes a lot of money to the wrong people. They have been hiding out in fear. She is starting to get harassed by these people looking for him.

This is the second time he has done this. Last time she borrowed money from me to pay his debts.
I’m trying to tell her, this isn’t her problem and shouldn’t be stressing trying to fix it for him. She doesn’t touch drugs or gamble. This isn’t her doing.
He’s not exactly the best partner. Cheating multiple times, secretly booked o/s trip and told her the day before he left, lots of lying. She says she will leave so many times, but never does. I just wish she would see her worth and be strong. She doesn’t deserve the life she is living (she agrees), but for some reason finds it hard to leave. She knows she should, but doesn’t.
He’s not violent at all. But he definitely manipulates her. He is quite selfish and unfortunately has these addictions that he can’t get a grip of. He acknowledges it, says he’s going to get help blah blah blah - never does!
She has tried helping him but I guess you can’t force someone to do something they’re not ready to do.
I’m just worried about her. It’s a pretty big deal when they have to hide because people are after him for his debt.
How do I help her?