My longtime friend told me he loves me but I have a boyfriend, what should I do?

I've known my friend since we were kids in elementary school, he told me he loves me and that he's felt this way for a while and had to get it off his chest. I told him I was flattered but that I don't feel the same way and love my boyfriend, he seemed really hurt by this but I had to tell him how I felt. He now thinks it's best if he keeps his distance from me as hee doesn't wanna get in between my boyfriend and I.