Need a Way to explain a break up?

Ok, I am in a small college right now and next year I will be going to the 4 year school which is farther away from home, moving up there, and getting a job and probably not going to be home very much as it is the next step in my life and I am moving on. I have been with my boyfriend for two years. We were planning on going together and moving in together and starting our life together. Recently he said that he would not be able to go and we would have to see each other once every couple of weeks. We are both very close, and if we don't see each other for even a couple days we get out of sorts and we each suffer major separation anxiety. We were apart for a week and i ended up in the hospital because i couldn't eat and kept getting sick. I know that we would not be able to last if we were apart like that and I told him that it would be better if I went and I would come back when I was done school and we could pick things up there with the thought that at least then we would be together when I am done school and we could pick things back up and spend the rest of our lives together then, versus me going up there alone and we end up driving each other a way and possibly breaking up over something stupid. I was only trying to look out for the best in our relationship. After much heartache and several breakdowns, we are back to the plan of going up together, but no matter how I try he doesn't understand my reasoning for my decision, and I need to find a way to explain it better. I don't want to pressure him into going up with me, but I know we wont last apart. Can you help find a way to explain it so he can understand it was only because I love him so much that I knew if we separated we would be back together one day. I love him with all my heart, and he is my one and only love. The last thing I wanted to do was to not be with him. I just need help explaining this to him. Thanks!