Hi R.,
While you think your girlfriend 'has NEVER done anything', you only know her side of it. No one truly knows what goes on in the privacy of another's home, or who got nasty first. It was quite the opposite with me, my version... I welcomed her with open arms. Then she changed after a marriage that I helped arrange. I don't even know her anymore. I have asked her many times, what did I do?, what went wrong?. She doesn't answer.
Tell your friend AND her husband that a good admirable quality is that of RESPECT.
It is the husband's duty to make as much peace as he can between wife and mother. It is perfectly fine to tell both not to disrespect the other. They do not have to agree, but he should not allow disrespect between the two to continue. It should be said calmly, strongly and definitively. He should say he loves them both, but he should protect both from harm and emotional stress.
Wife and Mom do not have to like each other, only respect. Each has the option of calmly walking away without engaging, and then if one tries to follow, THAT is where he SHOULD step in! If he has to keep them apart---HE SHOULD! A strong man can balance the two. Counseling IS in order............... or the marriage defintely will disolve.....a test of his true feelings is the final ultimatum.
A strong man can balance the two. My son apparently figured this out, and he is only 19. He tries hard to be fair and I'm sorry he is in the middle. As a result, we all do our best to be civil and polite. I don't want to fight and neither does she.
I want to see this marriage work for your girlfriend, so I cannot be flippant with the recommendations. I apologize for its length and wordiness. I wish them all the happiness they deserve, and the knowledge and help to which it can be achieved.
Sincerely,
F.