Relationships **** up my mind, how do I deal with this?

I mean, when I'm in a relationship my mind sorta changes its perceptions, and that kinda prevents me from growing as a person... When I am single I read a lot of books, watch a lot of movies as I dream of becoming a director one day, I like to draw, listen to music and think about life and philosophy in a very deep way. But when I'm in a relationship, which I usually am not, I happen to like the girl a lot and I have a strong desire for both of us to share a true connection.. I wanna move things forward, you know. And when this kind of attraction happens, I find myself to be so dragged and devoted to this relationship that I somehow lose myself... In my free time we're often texting, I start to barely read or watch movies (and those are the main things I usually do), let alone drawing or anything else. Even when I simply lie in my bed just to think, later on I realize the consistency of my girl's presence in my thoughts is just too high. As I think about it now, we don't do that much things together and yet I still seem to not be as interested in doing my things as I should be, you know... To me, constant self improvement is essential and is very important, but it requires you to be constantly focused on yourself, and maybe that's the issue.. When I am in love things just change, and I'm still very happy with my life, it's just that I'm not sure whether it helps or prevents me from growing on an intellectual level... Sometimes I think, that instead of being in an another social event, I could be just studying and gaining knowledge, and then it kinda feels as I'm wasting a precious time, you know. It just occures randomly as a thought, like somekind of a subconscious mechanism, which serves as a reminder of some sort, because I'm still happy with the way things are, but it's not the way i NEED them to be... Damn it's weird, love is something great, but it might as well be an enemy.
Any ideas how I should approach this..? I mean, should I tell this to my girl and eventually end the relationship or what? Because I know that when I'm single I can be much more productive... damn