I wouldn't say "move on," but I'd say "man (woman) up."

Your husband keeps doing this because you ALLOW him to. "1.5 to 2 years"???? What have been the consequences of his infidelity, and what boundaries, if any, have you laid out as a result of them?

Your husband will begin respecting your marriage as soon as YOU do, Z -- not a minute sooner.

Puppy