Advice needed

So I just started going out with this guy and he’s an amazing person but I’m scared. And I have so much anxiety from my past relationships and just with my self in general and I’m scared I’m going to get my heartbroken. I have talked about it with him periodically but never in a serious sit down conversation where it seems like he truly understands. He’s patient with me and so am I with him but I don’t want him to get tired of me. And I just want to know how to talk to him about it... or just advice for me to not feel so anxious when he doesn’t text me back or doesn’t show affection sometimes.