Shes Not Single (long Distance Relationship), I Like Her, Advice?

We are both in our first year of college, in different programs. We’re both 18, We’ve been hanging out alot lately, drinking and going to parties with friends and such.
Around the first/second week hanging out with her she added me on facebook and it says shes got a bf. The strange thing is, she’s never mentioned she had a BF or even mentioned him at all, and we’ve been hanging out for almost 3 months now.. Although once in a while it says stuff like “<3 Miss him" or somthing to do with him, on her facebook status, like once a month.
I know that long distance relationships dont work/wont work through the 3 years of college.. I want to be more then friends. She seems like shes really enjoying my company, i think she likes me, just the signals shes giving me, are not signs that taken girls give. We've even gone on a few dates just me and her, is that really normal thing a taken girl should be doing? We talk on msn like EVERYDAY, should i try to flirt with her over msn?
What should i do around her to let her know that I like her more then a friend? Any advice or views please tell me.

Long Distance Relationship With Crush On Another Guy?

I’m 21 and i’ve been in a relationship with my boyfriends for almost 4 years. I am away at college and the whole “long distance thing is really starting to wear me thin. I think we have good relationship, we’ve been through many tough times including helping me through a tough illness. We are very close and we talk almost every day, but I can’t help thinking about other guys sometimes. Our relationship is very serious and we have both talked about moving in together and marraige and children etc. We have a very healthy relation, but I have just been noticing this guy around my school that I am very attracted to, and having more self confidence, am dying to flirt with. I love my boyfriend but I can’t help thinking that I should date other ppl. I really don’t want to break up with him because I love him dearly, but I just don’t want to regret not dating other ppl, but I know to suggest this would crush him Any thoughts?