She’s a freaking socialite, isn’t she? She’s selfish to her core. I don’t think she ever wanted to be married to anyone. It would mean the focus wasn’t on her for half a second, and that would just be too long for her to endure.
I think she is alone, bitter and angry - she can’t take back the years she lost, her fertility, the lost opportunity she had to be a wife and mother (is there anything better than that??).
I bet she’d give anything to go back in time and choose a different path.