The 10 most-heard reasons both men & women give for breaking up:

Women -
10 - I don't trust you.
9 - We don't have enough in common.
8- We're not going to get married, so what's the point.
7- It's just not working.
6- I don't like your friends or family.
5- I need to concentrate on my career.
4- You're not mature enough.
3- You don't earn enough money.
2- This is going too fast for me.
1- I'm not ready for commitment yet.

Men -
10- We don't have enough in common.
9- I'm not ready for commitment yet.
8- I don't want to see you anymore.
7- We want different things.
6- I need to concentrate on my career.
5- It's not you, it's me.
4- We've lost the sexual spark.
3- I'm not attracted to you anymore.
2- I've met someone else.
1- It's just not working.