Really? Because it sounded to me like she was friends with this guy, and then started dating someone. Just because someone likes you but does not desire you doesn't mean that they have used you - more like someone has assumed more from the friendship.
But I agree, if you've got some sort of Hollywood inspired notion that every female friend you ever get will end up in a relationship, or if you only see females as potential girlfriends, then it's best to stay away from women and not put yourself in that position again.
My anolysis may be harsh but many women ,especially younger ones, just love to have a guy around to listen to their hopes, dreams, problems etc. Females love male attention, even if they never plan on hooking up with the person giving that attention.
And for a young naive male it may seem that she is interested in you but really you've been put into the dreaded "friend zone." Not that being friends is a bad thing, but you've been put into the category of "just a friend."
And that means one thing: chances are slim you're going to be hooking up.
When I say don't put yourself in that position I meant make your intentions clear from the start. Don't act like a friend, act like someone who is romantically interested.
As far as hollywood notions go, are you for real? Most guys who are trying to be "friends" with girls really are really trying to hook up. All the time? No. Most of the time? Yes.
If you doubt this, please put it to the test.
Ladies, take your best man friend and come on to him. I will bet dollars to donuts, and I love donuts, that the majority of guys will be down for it. Unless the lady friend in question is pretty busted. Dudes are skeezy horn dogs and will pretty much hook up if the opportunity presents itself.
Suffice to say, don't hate the players, hate the game. After all these years, that still has such a good ring to it.