Unhappy relationship

So last month I found out I was pregnant (currently 9 weeks) and this will be my third (first with my current bf). Me and my bf argue a lot and I'm generally unhappy in my relationship. We don't spend time together hardly anymore, Fight over every stupid thing, and I just feel like he puts everyone ahead of me and I'm just over it. He seems to blame me for every problem in our relationship. I'm not happy about this pregnancy at all bc we were definitely not trying! I am depressed and I just feel like I'm stuck. I was a single mom already to my 2 boys and just don't want to do it again. I don't know what to do..