Your friend doesn’t seem very smart. Married in the PH, cheated on her husband, moved abroad, and now wants a divorce. There’s no divorce in the PH, so she and her new man will have to try to get the PH marriage annulled (expensive). She’s better off just carrying on with her life as it is...

If she’s a US citizen now, she’s governed by US law, so she can file for divorce in the US, have the husband sign it, and then file it in our courts. If the husband will sign it, that is.

My understanding is that a marriage between Filipinos in the Philippines can’t be dissolved by divorce. A Filipino’s marriage to a ‘foreigner’ can, as long as the divorce happens outside the Philippines. For your friend’s sake I hope I’m wrong, but if not, she’s probably stuck. She might be able to get a divorce in an American court and remarry outside the Philippines, but she’d still be married in the Philippines and any later marriage would be illegal there. Annulment may be the only option. If it were me, I’d ask on r/LawPH.

Why would you help her? Are you the boyfriend?

Divorce doesn’t exist in the Philippines, so there’s no way for her to get one unless she’s willing to burn money on an annulment — and even after burning all that on legal fees, there’s no guarantee it’ll be granted. I hope the husband sues her for adultery