DH uninterested in sex...

We've had a pretty regular sex life (2-4x a week) until we moved. Now it's more like 1x a week and I feel like I'm always initiating. Also when I try to kiss him more than just a peck like when I get home from work he will kiss me back for a few seconds and then "suddenly remember something he has to do" or he'll say "oh I have to pee". Like he's looking for an excuse to get out of kissing me. It just seems really suspicious. I guess I should add some back story. Right after we moved I found out he had been talking to some girl and it took him 2 weeks after I asked him to delete her for him to actually do it...my mind can't help but wander towards the cheating direction. I would like to think he wouldn't do that but doesn't his behavior kind of add up to that...?