I'm very sorry to hear that someone hurt you like that. It is quite frustrating to make ourselves vulnerable to someone else by saying we love them enough to share things with them that we don't show to anyone else. When those feelings get abused or taken lightly, it's not easy.
I have gone through similar experiences. People can be very fickle about things that we might take most seriously. This seems to accompany youth most often, probably because some people confuse emotions with real changes in heart, like loving someone (wanting what is best for them always). He also may not have the discipline of heart not to resist some fears of commitment he might have, instead of talking through them with you.
My mom always used to say 'this too shall pass,' and I never knew how good the advice was until I was knee deep in woes. Make sure that you take care of yourself first. Realize that he is the one with the issues to work out, they are his problems. If he is vastly inconsiderate or hurtful, then at least you found out sooner rather than later. Love yourself, and be your own person not dependent on another for your happiness.
I hope some of this is relevant to your situation and I hope it's not insulting. I have very few 'answers' to life's questions, just some observations from personal experiences. It sucks trusting someone who betrays that. I usually take relationships very slowly for just this reason, and rarely put too much of myself 'on the line' until I know the nature of a person well.
Good luck, take care of yourself.
-Spooky