i was with my ex 18 months just 16-nealry 17 and i know what you mean hun.
i felt the same. like you sort of wnat to "experience" life a bit more, but then you don't want to lose him. kinda trapped...
due to unforseen circumstances (ie him moving to the usa) we had to splt up. i felt so giulty cos a part of me knew it menat i had a chance to be, well single.
and i had a good few months then met someone else, and stuff. i know its hard but maybe you just need to talk to see where you're heads at and what you both wnat from teh realtionship. my ex was 3 years oldr and looking back i know we wanted different things. i think it was too much too young.
hope things work out for you hun x