It sometimes happens to me, but then I find out that not every guy I meet is a person I need in my life, so I realize I don't really have to go chasing after every person that comes my way, because they won't be good to me. But you realize they're not so good for you when you know your priorities, if you think a relationship is way too important, even more than school, or your family, or even God, then you will have a problem realizing if someone is good for you or not.
It is true what they've said here already, that the love of Christ is the real solution, but don't understand it like the love of Christ will replace the love of a person and therefore you will feel you're ok and you don't need someone. The love of Christ is not like someone giving you chocolates or telling you you look pretty, you feel it in different ways; in my case, I started feeling it when I was ok with being home alone because my friends were at a party where they were getting drunk and stuff, it didn't make me sad not to be with them because what they were doing was not what I wanted for me, that was not what God had for me; and the guys they would meet there, I surely didn't want them either; at first is hard and it might feel awkward, but then, even when my friends seemed happy with their new acquaintances, one of them would end up with a broken heart, the other one would discover a bunch of things her "crush" had hidden from her, and that was how God made me feel I was being saved from it all.
Not saying everytime you meet someone you have to run away and lock yourself in your room, but then you trust God, and just live according to the situation He puts in your life, it will all go fine; then you won't have the need to flirt with everyone, you'll just talk with the people you feel comfortable with, you will get involved with the guys that come to you instead of you going for them, and it will work because when you don't search for it or chase the guy, you know that God sent him your way whether to teach you a lesson, or to put something into that person's life, and who knows? maybe something else.
The key is to relax and believe God can control it all, if you feel like you want to desperately go after guys, stop for a moment, breathe, and think that if you want something real, something that is worth it, and that will eventually teach you something and build you as a person, you have to let it be and let God do it for you, it turns out to be that He is the Creator of the universe and He does it all just a little better than you ever will. Hope you get my point.