Men are from Mars

Women are from Venus.
Idiot Girl is from Ceti Alpha V* methinks.

Background:
Boy meets girl. Alcohol is involved, and they pledge undying lurve. Idiot girl marries Twonko for the rest of time.

Except... fast forwards to almost two years ago, and Idiot Girl is not happy. The root of the problem is they are both selfish people who are only interested in themselves, and all they ever had in common was a love of getting totally wasted. And they don't do that any more. Idiot Girl wants OUT.

Twonko buys Idiot Girl out of his life, and she goes off, buys new houses(s), does other random stupid things, and we come to now.

Idiot Girl finds out that Twonko now has a new woman in his life. And she's totally devastated by this. Full on crying / no sleeping / drunkeness / destroy things.

This is the point where not being a) a woman, or b) insane I am failing to understand exactly what the problem is. Idiot Girl wanted OUT! Idiot Girl got what she wanted... Twonko is the inhabitant of Dumpsville, population you.

So, er, why is she remotely unhappy? Did she expect him to spend the rest of his life tying to "win her back"? I'm honest failing to understand how when she's got exactly what she wanted, what the problem is?

Answers on a postcard.

*2 geek points if you can name another Ceti Alpha V ex-resident?