How do I get over the fear of my boyfriend leaving me for someone else?

Okay, let me first preface this by saying that I am NOT a jealous person. I have guy friends and my boyfriend has girl friends and I have zero issues with that. He’s not a cheater, nor a flirt, or a womanizer. I have no issues with him having girl friends, looking at porn, etc. So that’s not my concern.

Ok, so let me give you some background info:
My boyfriend and I have known each other for 6 years. We met through mutual friends. He is 20 and I am 21 so we met when he was a freshman in highschool and I was a sophomore. We didn’t go to the same school but rather, met online on AIM through mutual friends. He lived 20 minutes from me. We talked online EVERYDAY for a couple hours for a year before meeting because, well, I was hesitant about meeting. I still considered him a best friend though because we had bonded.

We finally met and it was great. We hit it off and became instant best friends. We’ve been talking just about everyday for the past…5 years? We also have always gone out too…coffee houses, lunch, long walks, etc. He always felt really comfortable with me and I with him. We were platonic for years and it was just great…I’ve helped him through hard times and he’s seen me through hard times too. I eventually went out of state for college but we still grew closer despite the distance. He went to a local college. We still got together when we could. He had a 2 year (not sexual) relationship with a girl that he really was mismatched with and fought with ALL the time and I had 2 1-year relationships…both with older men (the last one was with a man over 30 years my senior). There were times that it both crossed our minds about getting together with the other but he was with her and so he didn’t let those feelings grow, and vice versa for me. Us being “single” at the same time never really matched up until this winter. We ended up kissing while reading poetry and we confessed our feelings and have been together since.

Okay, so it’s been a few months. Things are going great! We talk everynight (like usual) but he also drives to see me and I can drive to see him (I am 2–3 hours away for school). And of course, we spend breaks together.

I can’t stress enough how much alike we are. We are very different from a lot of couples. He’s not a macho guy (he’s like me, average-looking to most but I find him very handsome) and doesn’t like girly girls or macho guys. I’m fairly androgynous. He’s had a few crushes before and they were always on girls like me. He’s SO picky…he won’t date a girl unless she’s extremely intelligent, must have a wide variety of interests (like he does) reads a lot, is a conservative Libertarian, but must be an atheist, NOT a girly girl, can’t be clingy/too emotional (he’s VERY logical), likes the same sort of music that he does, etc. Basically someone to learn from and teach stuff to, in his words. And this describes me to a T!

So what’s my deal, right? I’m not worried about him cheating or whatever. He’s been HUGE on monogamy ever since I’ve known him and he used to be in a band (we weren’t together then) and girls would just want to do him but he would just push them away and say “No! I have a girlfriend! Back off!” Despite all their fighting, he was very loyal to her and never had eyes for anyone else. I really respected him for it. So I’m not worried about him. It’s just…I think I’m falling in love with him! It’s scary! Do you know how long it’s been since I have been in love! About 6 years!!

I love my time spent with him. It all feels so natural and fun and good. We have our exciting times and then “relaxed” times. We haven’t had sex yet (he’s a virgin) but we plan to soon when we are ready. I’m REALLY falling for this guy and I know he’s falling for me too. Our relationship has always been deep and we have such a long history…now it’s just developing and it’s…wow.

Anyway, ONTO my concern. He’s going to change colleges. He’s going to go to this one in PA, about 1–2 hours from me. He’ll only go there for 2 years and is rooming with his best friend of like 10 years. I don’t know what I’m so worried about but I worry that he’ll somehow go there, meet someone else, and leave. I’m SO scared of getting my heart broken, you have no idea.

I don’t feel the jealousy urge, or an urge to control him from seeing women. That’s ridiculous. But I feel sadness at the idea. He tells me that he wants to be with me while he’s at college because a) we’ll both have cars b) we’ve been long-distance best friends for years and never grew apart and c) we both are planning to come back to the city where we are both from. Cause that’s where our homes are so we’ll be back for breaks and such and we’ll be back after college (he’s only going for 2 years – I have 1 year of school left).

BTW, he’s been to college parties and he hates them. He’s a very old soul in what he likes to do and is much more of a one-on-one person, along with lots of alone time. He’s so much like me. We really complement each other and it’s been amazing to see how we have grown together through the years and not apart.

GAH how do I shake this anxiety? It’s not all consuming or anything, but it nags at me. Am I just being stupid here? I am not telling him my fear because I KNOW I’m being neurotic and he shouldn’t have to hear that.

Please advise. Thanks.

Oh, and I’m sorry this is so long. +1000 interwebz cool points if you read the whole thing.