She has no money and no family. He destroyed her life and a support network that was already so strained and unreliable to begin with—and he is an ultra wealthy egomaniacal coward and psychopath that doesn’t actually understand the first thing about human relationships which is why he could go thru with it, be all surprised when it made him feel horrible, and then STILL believe he was entitled to hurting her and having her. Powerful lonely morons are the absolute fucking worst.
Girl, I got it.
I am just saying if she can't live how she want, which is away from that psycho, I would suggest her to pretend forgiving him and even getting back together and letting him drown in that illusion of happiness until the day he comes back home and find her death body.
I am pretty like that, and I would literally sacrifice my life to make him go crazy and be miserable forever.
Meanwhile, the way I wish for a car to run over him...

She needs to file a restraining order on the ex-husband
Although knowing Korean laws for stalking is an absolute joke the judge probably won't take her seriously