Scared to go out with anyone ever again...but I like someone!?

I never usually ask questions in this category, but here goes...I'm in my freshman year of college. I broke up with my long-term (over 2 years) boyfriend, who I loved very much in a high-school way, before leaving for college. It was mutual, but he more or less stopped talking to me about two weeks after we parted, which really hurt my feelings since we had basically been best friends for almost all of high school.

Anyway, so that was 7 months ago, and I haven't really had any serious crushes on anyone at school until recently. There's this guy who's in a bunch of classes with me this semester and we've been hanging out a lot lately in groups, and I really like him. He's really smart and funny and cute (or at least I think so :) ) and interested in the world and we get along well. I'm just scared to pursue anything because... 1) He has commitment issues (according to his twin brother). 2) He can be kind of mean/impatient/easily irritated with people sometimes. 3) One of my friends liked him, and even though she says she's over it, I don't want to hurt her feelings. And 4) I don't know if he likes me back. He's a little bit of a flirt and so when he smiles at me or compliments me or laughs at my jokes or glances at me in class I don't know if he's just flirting or if he's actually interested. And my biggest fear is being rejected and hurt again by someone. It made me feel worthless the first time and I don't want it to happen again. Not to mention it could be awkward if I approach him and it doesn't work, since we work together in the theatre department.

What should I do? Should I continue to spend time with him in the (possibly futile) hope that something happens? Or should I remain friendly but try to get over this crush thing? I've got a lot on my mind! Please help!