No love or sex

Hi girls, so I have been dealing with a problem and it's driving me crazy I just need to let it out. My husband has been lacking sex, he hardly ever kisses me and if I try to even reach for his hand he swats me away. I don't know how to deal with it and I can't help but think he's cheating on me. He hasn't always been this way, he used to like for me to hold him and now he can't stand it. Everytime I try anything lovey he groans in the most annoyed way and tells me to leave him and just enjoy whatever we are watching. Anyone have advice to help us out?