Amy,
I could go on forever about life in the military but I will keep it short and sweet. I spent my first 8 yrs active duty Army and then transferred over to the Coast Guard where I have been since '99(15yrs all together). I met my wife between transferring from the Army to Coast Guard. Even though I was familiar with the military life it was a big adjustment for my wife. When I reported to the Coast Guard I was due to go on patrol within a couple of weeks. I would be gone for three months. My wife was flipping. She had a hard time trusting me and always thought I was cheating on her while I was gone. Well this went on for atleast a couple of years. After a year or so of me being gone for months at a time she soon adjusted to the life and our marriage became stronger.
As I said I could go on forever, but I won't. The military life and relationships could be very difficult at times, but it's up to you and your partner to make things work. Don't be affraid to ask questions about the military there are alot of support groups out there too that could help.
If you believe you have a strong relationship don't worry to much. Right now your boyfriend has more things to worry about than worring about you worrying about him(did that make sense). Even though you worry about him try and not to show it to much. He has more important things on his mind right now. You have to be just as strong as he in your relationship. If both of you do this and not let the military ruin your lives you will both be fine.