Boyfriend issues

So last night I decided to text my boyfriend and just say im sorry for a whole bunch of things. When I got up today I decided to wait for him to text me because I feel like I always have to start our conversations for us to talk. I waited all day, and the first thing I got from him around 6:00 PM was sorry you can listen to music. Around an hour later, he says he's sorry for everything. So then we started talking in long texts. He then tells me that this really close guy friend I have which I can tell almost anything to, that he things that I'm cheating and that he knows I'm not but it seems like it. So in the beginning it was me who needed him and stuff and in the end I was the one who was saying sorry. I've been thinking about this and it seems like ever since we had sex all we do is fight. Like it seems before the sex we were really happy and always laughing, and now it's just fight after fight and I don't know what to do. Please help.