Is it normal to accuse my boyfriend over everything?

I agree with lc1988, if you have trust issues when you're in the same area, you will almost certainly have trust issues when you are long distance.
I have a few questions and I'm not trying to pry you can ask yourself these without posting, what made you think he was cheating in the first place? (was it an event or something that happened are you just afraid that it may happen?) Why are you accusing him of bad intentions? (did he do something or is he just being very secretive, is he doing things behind your back that you don't approve of?) Is there any way you can just go to a college close by, if you want it to work then I suggest staying near him, but of course if you can't well I'm sure you'll figure something out (long distance relationships are hard to keep going, especially with trust issues; it seems like you really want this to last and work since you're taking the step of going to a therapist)
Relationships are going to have their ups and downs, everyone goes through them; it just depends on how you deal with the issues at hand that keeps it going healthy. It may be bliss in the beginning, you're getting to know each other and haven't really established anything yet, then you get comfortable with each other and the flaws and such come out and you get to know each other better, talk to each other you may not like what he says, but if you listen you may be very surprised at what the other one says or thinks (remember people are not mind readers and if you haven't explained what is bothering you (in a civil manner not a heated argument)he may not know what is hurting you or causing you to have these trust issues.
If he says he has good intentions, he may not realize that certain things he does or how he acts is hurting you. Not sure if I helped at all, good luck and I hope everything works out.