I'm thinking at some point in time someone planted these thoughts in your mind. You eventually believed what you were told. You need to look at yourself in the mirror. Really look, and see what others see. You will find you like alot more about youself than you first thought. You need to search your soul for the things and feelings you have that make you special/ who you are, Everyone is unique and special in their own way. The only person who really knows you is you, so the only person who can help you is you. When you finally love yourself, you can then love someone else.

You can start by challenging the notion that low self-esteem is "preventing you from doing so". I'm not saying it's false, I'm not saying it's true, but I am saying it's worth a second look. While you're at it... while you're busy challenging that idea, you might as well extend your reach a bit and challenge some other things: your ideas about who you are and what you look like, your ideas about what you think you SHOULD look like, your notions about what other people expect you to be, your ideas about what girls like, etc. Heck, as long as you're going that far, you might as well question everything! Then, just to keep the theme going, it's a good idea to start trying to catch yourself in those automated patterns of thinking, things like "I'm not good enough", or "they won't like me unless...", or "I should really be more like X...". Maybe, if you keep up this approach, you'll find something interesting happening. Maybe you'll notice that a lot of how you think and behave is more machine-like than authentic... more pre-programmed than anything like true thinking. Just maybe you'll end up with a certain kind of "breathing room" from your incessant and insistent thoughts, and a bit of freedom to -- I dunno -- just be yourself. If that doesn't help, I guess you can always just give up and do positive thinking or some other dull-witted strategy. :)

you have already conquered the biggest battle- that is.. recognizing that you might have low self esteem. most people haven't even gotten that far. so congratulate yourself on that, and reward yourself for realizing that, too. do not let your mind play tricks on you. you can accomplish anything if you set your mind to do it. give yourself reachable goals, and when you achieve them, remember to reward yourself, and remember very clearly how you felt when you did what you set out to do. that will bring out that outstanding self that is most definitely tucked away somewhere. and remember, people love you for who you are, not for what or who you want to be.