10. He suddenly has to work a lot more.
Maybe he really did get promoted. Or maybe he just says he has to work late because he’s going to meet someone else.
9. He seems to misremember things or forget details.
He mentions that time he took you to dinner at that place by the river…except he never took you to dinner at that place by the river. He remembers it because it happened with some other woman.
8. His weight or appearance suddenly changes.
If he’s suddenly getting in shape or dressing differently, it could be a sign that he’s primping for someone else.
7. He avoids being intimate.
It could be because he’s getting it elsewhere, because he’s paranoid that somehow you’re going to be able to tell, or he just no longer feels that connection with you.
6. He’s secretive about his finances for no reason at all.
Maybe he doesn’t want you to see the receipts from all those dinners out or nights at a motel. 
