It isn't just women that act like this.

And I don't act like that, I try to at least be friendly with somebody I have just broken up with.

I have seen friends become very cold and aloof, just because they do not want to be hurt again (male and female), but have never seen anyone treat their children bad. I am sorry to hear that.

Women change when they end a relationship because if you've been wearing whatever it is for that long, it needs a clean.

Ekans, you are a squaddy if ever I've seen one! Tell me I'm wrong.

spdarkhorse is completely on the ball, it is often a defence mechanism. It's very hard to break up with or do something bad to someone you like or respect. So you find reasons to dislike and then hate them, it makes it easier to do what you have to do when you demonise someone.
And it has a snowball effect.

Also, its a very uncomfortable feeling when you stop "fancying" someone you were very intimate with.

Plus you probably have a wicked mother in law feeding her poison against you (just an assumption). Makes the mother in law feel important and needed again. The two of them are probably closer than ever. (I know I'm generalising, but that's human nature)

Possibly.

And funnily enough..I listen to them when they warn me now..!

I'm always blunt with people. If I think somebody is a bitch/idiot/asshole - I tell them, and I also tell the person they are seeing!

I don't have many friends.