I know my boyfriend cares about me, but he thinks he loves me?

We've been together for three years. We've lived together for two. We're both in our mid-twenties. I thought I was in love with him. He thinks he's in love with me. Over the past few weeks, though, I've realized that he doesn't know me at all. And as much as I've tried to make him happy and have thrown energy into being a good girlfriend, I don't really know him that well either. The problem is, he thinks that everything is fine. He is very content with the "love of his life" inciting absolutely no pion in him, and being his perpetual roommate. And I (who have thrown every discernible definition of pion into our relationship) am getting four hours of sleep a night since I realized this. I love him dearly, but I don't even want to sleep in the same room with him anymore, as I feel suffocated by this realization. I want to talk to him, but I have no idea how to start the: "You know how you think you love me? Well, I've been thinking, and it turns out you don't. Thanks for caring about me so much, though." talk. What now?