CAMO - Connecting All Military Others
He will be going through a really hard time and will need all the support you can give him. The first two weeks they are unable to write (and I actually got my first letter from him 3 weeks after he left). I had a really rough time getting through the first 3 weeks after he left. But after that you kind of get into the routine of writing and waiting to hear from him. They have a tendancy to hold mail at times for them. And letters that you write will cross (meaning he has a possibility to recieve a letter you wrote a week ago after he gets the letter you wrote this week and the same will happen for you). I was looking online at some helps for while he was at bootcamp and another lady suggested that you number your letters and he do the same. It really came in handy for us because there were times where he would recieve 3 letters from me at one time and same with me. Some guys have a tendency to change their appearance (either gain or lose weight). Expect the first two weeks to be hard, really hard, but know that things will get lots better after that. And this probably could go without saying but above all Don't Cheat on him. Nothing will make basic training harder then him finding out the girl he thought he liked/loved doesn't feel the same way. And if you think you can hide it from him, they have a way of figuring it out.
I'd say I got on average 15ish letters while my fiance was in boot camp. Since he was there for 13 weeks so I got at least 1 a week, but sometimes I would get 2 or 3 a week, depending on what he's going through at the time. But I would write to him almost everyday to make sure he got letters often so he would feel a little bit of home was with him.