Thanks guys, I'll ask about rescue remedy and then try it if they say ok.
I can't take him to the vet thanks to how much it stresses him out. I might go get him a heated bed and see if that helps too.
He is my cat, so has always been more affectionate to me, but now he loves the whole family a lot. Last night dh and I were watching tv on the lounge, we were sitting right next to each other, and the cat comes and sits on top of us, pushing a little space in the middle to lay down. I picked him up moved him to my side, he looked at us and went straight back to the middle, and he'll do that every time now.