I found some e-mails that he sent to a certain girl last week

Well, if you were looking through his email you must of felt there was a reason. I went through my Ex's cell phone and found text from a girl who wanted him sexually. I knew something was wrong. So, you know you have to let him go. He wants to date someone else. You need to find someone that will care about you enough that won't cheat. You can do it. In the long run you will be better off, and you will be able to look back and call him a jerk. Cut your losses. I know it's hard. Easier said then done...But you can do it.

Stop spying that's what psychos do. Now that you know though, leave.

Leave now and you'll be laughing when the other girl is in the place you are now. And if that never happens, good for him, not for the cheating on you bit, but for finding someone who's good for him like you couldn't be. You'll find someone better for you than him.

He's a cheater and a player. You don't need to stay with him and have your heart broken this way. Even though you say you love him, you have to leave him. Its obvious he doesn't love you the way you need him and love him.

Well of course, break up with him. It says you're under 18. You got plenty of time to meet other guys out there. I know that's not what you want to hear, but even if you were to continue with him, at some point he will end up breaking with you, or cheating on (well, he is cheating now I guess), so best to cut the damage and walk away now. By the way, even though you say you love him so much, when you turn 23, you will look back and you will see how your definition of loving somebody has completely changed.

If you are his girl you should be in the throne but obviously this girl is. Its not worth battling over a guy who doesn't feel the same as you do!