Roommate+ feelings + sex = confusion

I moved apartment in September and I was supposed to look for a place with my flat mate and his best friend, a guy that I've never met. My flatmate though, decided to go back to his county and leave me and the other guy - that I'll call john - on our own to find a place. As we were looking for something for the 3 of us and now we were left alone, we needed to find something else on our new reduced budget  - damn london you are expensive as hell- and quick!! . So, Me and John had 4 days only to find a place and move out from the other apartment. We agreed to split the price of the rent and share one room, as we got to know each other and we got along pretty well It didn't seem a bad idea. But, the only place we found had one bed only. I guess you know where I'm going now. It didn't seem a bad idea in the beginning, we kind of liked each other a bit, but nothing had ever happened. Then, the second week, we were just lying in bed and, we kissed. All stared just as a game and then a lot of other things happened in the next 6 months 😅... we are still roommates now and, at the eyes of others, we look like a perfect couple. He's the sweetest person that I know, he cares a lot and so do I. The problem is, when I've told him that I have feelings and he told me he cares a lot and I'm important for him, he also said I could never be his girlfriend because we don't have a lot of things in common. So, my quesrtion is: Am I the only one that thinks that, when I feel good with someone - for a long period of time, like 6 or more months, living together without killing each others - I don't really care if I like reading and he likes going to the pub? What shall I do? I've told him I'm not pressing on having a boyfriend right now, but... I kind of really really would like this to happen 🙁 maybe I'm PMSsing or maybe I'm just tired of having to deal with this situation. We love each other, we care, we have sex, we go out together and we live in the same house. I don't really want this to be the sad story of me and the so called John, the two that loved each other but, neve got together because she liked books and he liked beer. 

Help!! What shall I do?🙁