I used to be cuddly and want sex, now I don't like being touched at all.

I'm newly married (May 2023) . Before we got married we had regular sex, we were very affectionate. Now I can't stand it. I have asd and my partner hasn't. He's really understanding, but I hate rejecting him all the time. The sex is amazing when we do, but the kissing and cuddling makes me not want to.  

How can I change this ?