“When a woman suddenly wants to separate, for no known reason, it’s usually because she is being unfaithful and thinks she has found a better option.”
Excellent post.
“Best friend” means she no longer finds her husband sexually attractive.
It would be very unusual for her to go for divorce in that situation (especially with young children) unless she had already started another relationship behind his back.
It is also highly unlikely the “new guy” is interested in a long term relationship with a women with kids—of course he hasn’t told her that...yet.
;-)
The best friend is the same as saying, I love you, but I’m not in love with you”.