Am I in the wrong relationship or is this my anxiety destroying things?

So lately I have been deathly afraid and obsessed with the idea that I might not want to be with my boyfriend anymore, that we are not right for each other. I find myself sitting around, picking out all of his flaws, all of the flaws in our relationship. Then I think that that means we should break up, and then I get really sad and freak out because I don't want to lose him. When I obsess about this I dont feel as connected to him, I feel overtaken with worry and I cannot enjoy myself. Is this me falling out of love? I know that I love him though, and the idea of losing him makes me sick. I just cannot stop obsessing. I have depression and anxiety as well. He is my boyfriend of a year and a half. We are both going off to college soon and we have decided to break it off when we go away. It is going to be really, really hard. I do think that it is the right idea for now, to become our own people and not be tied down and then maybe get back together at another time. Either way this relationship means a lot to me. I am probably thinking too much, but I dont want to ruin the last two months with him. I just want to enjoy him company. I dont really know what to do???