PLEASE HELP??? WHAT IS MY BOYFRIEND TRYING TO DO?

My boyfriend and I live together. We love each other very much and we are getting married soon. He said he is very possessive of me. I don't understand, why does he tell me one thing and then say something else. For example, he will tell me that he knows that I need time to hang out with my one friend, who is female, of course hanging out at our house when he's at work cuz i am not allowed to hang out somewhere else other than our house. I have to call and get his permission first before she can come over. If she just shows up at the door, I have to call him and get his permission for her to stay as well. She has to leave before he gets home of course, cuz i have to go and pick him up from work right on the dot, not a minute later. And then after he comes home, he seems kind of snappy towards me. He doesn't yell at me or become violent or anything like that, it's just that something doesn't seem right. It seems like he's mad at something but he won't tell me what it is. I think it's about my friend coming over. I used to have 2 other female friends. But now, they are not allowed to come over and I am not allowed to see them and talk to them. Because supposedly my boyfriend says that they are a "bad influence on me" and they are "bad friends." Now I only have one female friend. I have never done anything to make him not trust me! Can you please tell me what's going on here? What is he trying to tell me? Why am I getting this kind of something is not right thing? What is trying to accomplish here? PLEASE HELP??? Thanks!