My anxiety makes me worried about my relationship

I’ve been dating this guy for a few months now and everything is going absolutely fantastic. However...my anxiety keeps making me worried that this isn’t going to work out. There haven’t been any signs that it won’t work out, but at the back of my head I’m terrified. None of my relationships have worked in the past and perhaps that’s why I’m scared. I really really love this guy and I know he loves me too.