Bollenbach,
I'm fairly new on these forums, in fact this is only my 2nd reply. However, I'm familiar with jealousy.
Now, I apologize that I don't know if you are male or female, so there are going to be he/she's in this reply. You also haven't indicated whether said person has given you a reason to be jealous, so this is just general advice...
My best advice is to face the problem of jealousy head on. Otherwise, it will eat at you like a cancer. I too ran into this when I did some time in college. My g/f at the time was really outgoing, and loved the attention of guys, and although she was faithful to me, I never fully trusted her. And to prove how deep jealousy goes, when I think back to my relationship with her, I still consider the possibilities that she cheated on me (it's been over 8 years, now.
The lesson I learned is if you like that person, give them the benefit of the doubt, and let yourself trust them. Because of my jealousy in the relationship, I lost the girl, and to this day, I really don't know if she ever cheated on me or not. The result.....No Girl and No Answer. Had I allowed myself to trust her, I might still have the girl.
Especially, with the fact that you are in a college relationship. I'm assuming that the other person is attending college as well, and he/she is going to have all kinds of contact with the opposite sex, be it study groups or just hanging out with friends. You cannot be worried about what he/she is doing or jealous everytime he/she goes out or to a study group. This will drive you absolutely insane.
I've rambled, and this post may not make sense. But, Take away one thing....Either trust him/her completely or it's not going to work. Also, Don't be like I was and always try to be on the lookout. I was convinced that if she was going to cheat on me, I'd see it coming and would be ready for it, but in the end I could really never trust her.
Cure that "cancer" before it develops into something worse. You can get through it. I did, and no longer have any jealousy issues. I know that if my sig. other cheats on me, then thats the way it works out. There is really nothing I can do to change that, if she is the type of person to do that to me. And if she is, then, I'll be better off than the next guy.
-Justis