Clearly none of my business, but starting to feel concerned for her.
I have a small friendship group with a pretty active social life, including lots of long weekends away.
The core is 4 single people (2 men, 2 women) 2 married couples and a married man who almost always comes without his wife. At various times friends of friends will join us and obviously not everyone comes to everything.
Friend's DW is very welcome, when she does come she's sociable and appears to enjoy herself.
Mostly though he says she prefers having the house to herself and him going without her. This is most weekends, sometimes twice in a weekend, although he is aware when it's been several weekends in a row, and they do go off and do things as a couple fairly often too (no children). Sometimes he'll decline on a "better not" basis, but she'll tell him to come.
In the face of it, it seems a perfect realtionship, happy together but enjoying separate interests too, and I can't quite put my finger on it, but lately I feel like something's not right. I don't know her as well as him, but she's lovely and I'm a bit worried for her but can't place why.
FWIW, he is always perfectly well behaved when out with us and she has nothing to worry about on that front.
Is there anything I should do?