I can't understand what her problem is--she really sounds selfish.

A friend of mine was in this situation--her widowed mother married her widowed father-in-law--everyone was happy about it. There were some good natured jokes about incest as her husband had become her brother --but both of them thought it was a hoot.

My friend was happy about not having to decide (or fight) about where to spend holidays--no more parents or in-law choices!