My daughter wants to move back?

Sounds like her husband is the problem. If he won't compromise then it looks like your daughter will only have two choices. Separate from him, or stay with him and be miserable. I doubt this problem is as much her being homesick as it is her husband not willing to compromise with her. That is probably adding more stress. See if she can come home for a vacation for a few weeks and take a break from where she's at now. It should clear her head and help her to realize what is really best for her. I'm not for divorce or separation, but if she's never going to be happy where she's at now and her husband won't compromise with her, then I think that is the bigger issue, and she needs to do what is best for HER.