I'm Going To Loose Him In Two Months Time.

i've been with my boyfriend for about a year and a half, he is my first love and i would give anything for him. I am a year younger than him in school so in two months time he's going to university in london. london is not far from me at all, about an hour on the train and tubes, but i don't think its going to stand. he can't emphasise very much and doesn't think about things when he says them, he told me that we probably wouldn't be able to stay together due to his 'high sex drive' - not exactly what you want to hear my situation. I do, however love him, and he does love me, it sounds silly though as he wants to sleep with other people. He told me that he does want to stay with me, and he never wants me to leave him and that things will work out eventually. Which i hope is true... i just don't now what to do, do we try to stay together and see how it goes, or do we change the way our relationship when he starts, to more of an open relationship? I just don't know how i'd feel about him sleeping around with other people, and there as so many people there, its going to be even more heart breaking if he meets someone else he wants to be with...
we have broken up before and remained as friends, still hanging out together and our friends who are the same who are also going to uni in london this year.

i am looking at universities in London also, but i don't know if its because i want to go there, or if I'm being too hopeful in thinking that if I'm in london also, that we can pick up where we left off...

has anyone else been/ is in this situation?