I really need help on this... suggestions welcome from everyone?

OK..so im in college n im really young compared to most of my clmates. unfortunately this means most of the boys i come across are usually older than i am. so last semester me n this guy really hit it off and we been flirting ever since and it kinda developed into some weird kinda relationship. n i say weird coz we have completely different personalities since im more outspoken n he's more of the quiet type, its long distance since i moved back home for the summer n he's 8 yrs older than me. regardless of these differences i really like him but i always feel like im giving him more than he's offering me and it doesn't help that he is always flirting with this other girl who's his age on a social networking site (no names) but he tells me that im the only one he's into. should i be worried coz i don't want to be all into him n end up heart broken. and is it even a relationship worth going on with?