This sounds like you jsut had a lot of very bad luck with this, and it's not your fault. Just don't give up; there will definitely be someone out there for you. My advice will be kept brief, so that you don't misinterpret it, and it seems like a surprisingly simple situation.
1) Don't be desperate and go for the first girl that is hot; take your time, and you will be rewarded.
2) While you wait, find something to use your time that doesn't involve girlfriends: music, art, books, anything. If you're lucky, you could meet someone in this way.
3) Tell her how you feel early on next time. Even if she doesn't feel the same way then, chances are higher that she will soon share feelings. This may not apply, but it worked for me.
4) Don't be annoying/desperate. Luck will find you, and things will get better. There is no need to rush anything, and doing that will both turn girls away and not show who you truly are as a person.