Aww I totally know how that feels.
I read somewhere that we are actually biologically wired to "love" someone for the amount of time it would take to make a baby and take care of it until it would walk/feed itself. Apparently about 3 to 5 years.
So maybe it's just that initial hormonal love feeling that's gone. I was in this same boat, though, about a year ago, I had been with my boyfriend for 4 years, and we had taken month-long breaks during the summers a few times... But I really felt like I didn't love him anymore. I was sure that was it and it was over FOR GOOD this time...
I was single for 6 months... Longest break yet... But winter came around, and thank God he still wanted me back, because I wanted him back, too. We've been together for a year and a half since... Making the total time together like 6 years.
Point is, you never know what you're going to want later, espcially if you're like me, a "fickle female" or whatever you want to call it. If you don't want him now, maybe you should take a break and see how you feel without him. You'll either be glad you did and move on, or be glad you did and realize that you really do love him still. The only risk is that you may not be as lucky as me and have a guy that couldn't move on.
Think about it and good luck!