Girls have a greater tolerance for pain. They can handle more.
Errm... Guys like girls. They like looking at them a lot. Not all guys do that though.
same reason guys do
They are just different. Guys take longer to mature than girls do
girls: girls can take a birth control pill (unless of course you want to have children) guys: guys can wear condoms
We fear rejection.
The person who takes the breakup harder depends on the person in the situation - it is not simply guys or girls.
Some girls are just too desperate to wait for the guy to start the relationship, so they take charge and ask them out themselves.
That is actually a common stereotype. Many girls do not like tough and athletic guys. But if I had to say why, girls are generally attracted to "manly" men or someone that they believe will be able to take care of them.
When guys take it way too far when they flirt
Most guys don't understand what girls want. They just do what they think you like. They will try to look tough (which most girls do like.) Yet I find some guys (not often), wouldn't do anything for the girl they like if it means losing their popularity. Some guys, understand what girls REALLY want. Knight in Shining Armour stuff. They take an interest in what the girl has interests in, and trys them. It's usually these guys who will get the girl.
You work it slow, and take it easy. Girls love funny sensitive guys.
Because they stole something very precious to them. Their virginity.