I'm finding it really hard to stay committed, what should i do?

First you need to be honest. You need to tell your girlfriend how you are feeling. Make sure that she knows it has nothing to do with her. Then you are really going to need to work on this. Here is the problem, if you can not commit then you should not have a commitment at thia time, all that this is going to do is cause pain for both of you if you end up hurting her (cheating) that is going to ruin any chances at a trustful relationship with this girl. I can tell you that if you cheat you two will deal with that for the rest of the relationship if she stays with you. So you need to make a choice you can either have her, or you can run around sleeping with a bunch of different girls. What I can tell you is for one if you choose to sleep around you will regret this decision, you would be giving up the first girl you have ever been able to connect with. second is you can get it with the girl you are with, so why do you need to get it elsewhere, BUT with someone who you love and loves you back is way better. I really hope you make the right choice. You just need to learn how to control your urges. Good luck don't blow it.