Is it normal to be in a relationship with nothing in common?

Im 17 and have been with my boyfriend 6 years.. yeah we were 12 when we got together and are now nearly 18! When we were young, our differences weren't so apparent. I'm going to University to study politics and Spanish and i love talking about things going on in the world and also about emotional everyday crap. My boyfriend loves music, with a passion. But this is all he likes. I find this really hard to relate to, and as we have gotten older we have less and less in common. We live really close to eachother, like half hours walk? but when we speak on the phone its soooo boring. Its just like hey, how are you, what did you do today, bye. We have literally zero in common. When we are together it is TOTALLY different. When he comes over my house we cuddle and kiss and laugh loads and talk about stuff. But is that really enough? Especially after 6 years. Also, he LOVES his friends, and i've always known they prioritise wayy over me. If we've planned to have a sleepover one night, but then the guys are doing something, he'll ask to change our night. It really makes me upset because we only see eachother once a week. (im in sixthform, he's in college) yet he sees them atleast twice in the week and all weekend. If we have a sleepover friday night, he'll be with them saturday, saturday night and sunday you know? it swaps like that. Its just so insulting that after spending THAT much time with them in the week he would still rather spend time with them than me. But i love him soooooooo much. He is just so cute and iknow he would die for me tomorrow without a second thought, its unconditional love. But is that enough? Im always upset about how he brushes me off when a better offer comes along and he never takes me out anywhere .e.g. he forgot to give me something on valentine's day, even though i made a meal from scratch at my house (which he didn't really appreciate). When i go to university and we'll hardly get to see eachother (its 3 houes away) im worried our relationship wont stand a chance. I really want some opinions or ways to make it better :( he's really such a great guy, but does he really have room for a girlfriend in his life? Should i want out?