First off, bullying is much rarer in college since students have matured a lot more and the majority of them are there because they want to be. It's a completely different environment to school.
Secondly, bullying is tough for anyone (and it isn't just introverts who get bullied). "Ignoring it" doesn't always work either.
I would recommend taking classes in karate or some type of self defense.
Not just in order to be able to defend yourself should you need to (which is a good idea in today's world anyway), but you will find that it completely changes you; your confidence, your posture, the way you carry yourself. You will be much less likely to become a target in the first place, but IF you are... You'll be able to handle it.