Should I stay with him even though he loves me more?

I have been in an on again off again long distant relationship with my boyfriend for five years now. I am incredibly attracted to him and when we are together we usually don't leave the bedroom. He has matured so much over these years and has morphed into my idea of the perfect man. The only problem is the way he feels about me frightens me. He loves me so much and I'm afraid I don't feel the same. But I'm not sure exactly what it means to love someone; therefor I could feel the same. I was hurt very badly by someone when I was young and since then I have always been a sort of emotional shell. Any way I am hoping someone can give me some advice on what I should do because I feel if things keep going like they are, we will get married and I will make him miserable.