Significant Other not really what we are

I've started talking to my significant other around December of 2013 &we've been dating since April but in the ending of May we broke it off &the ending of June he came back into my life. We've been trying to get back what we had but he told me that he was cheated on for a whole year & that he hasn't full recovered so it's kinda hard for him. Anyway we both lost our virginity to each other &we had a pregnancy scare &i thought that he was going to leave me or he was going to want me to abort the baby but he didn't. He was actually really happy &we talked about what we were going to do &we even talked about names, he was very excited. we ended up finding out it was a negative &I was happy &he was kinda sad but he still stayed. Anyway back to the topic; he comes visits me, he gets along with my family &we go out during the weekends &we act like a couple but we aren't one. Every time we have sex we go like 2 days without talking &when we txt is always so dull. I don't know what we are, when I bring up the subject of boy/girlfriend he always acts all weird & when he brings it up I feel weird cause he never wants to talk about it. Every time we have sex it makes me question what this is.