It depends how far away you are from each other. My boyfriend and I are an hour apart and sometimes it's been hell but we seem to be doing okay and after 2 years apart we're still together. We manage to see each other most weekends but that's because an hour isn't exactly that far away.
My advice is to be honest with each other all the time, if you feel that you are starting to become distant then tell each other straight away and get it sorted, otherwise things just go tits up lol. Ring each other at least once a week and text each other every so often (not excessively).
Youy can make it work if you are both committed and love each other.
How do you think you'll do?