I'm not even sure that my wife wasn't going thru some sort of life crisis 5 years ago. In fact, I was told by many people (some of whom were very familiar with my sitch) that she WAS, in fact. She certainly had a lot of the typical "signs" -- got a tummy-tuck, drove a new BMW, was pursued by (and ended up having an affair with) a 29 year old (when she was 47), etc. She went from living with her parents to living with me when we got married, and you could certainly make a strong case that she was "replaying" that part of her life that she was never allowed to have -- that I did have, when I was off at college and the years just after.
If it's true that she was, however, then all the more "hmmmmmm" that she was able to break out of it so quickly.