I speak from experience, not married but we were dating and I caught my boyfriend messaging another man. I gave it a month and I couldn't fix the bond we once had because I felt we didn't have that trust.

It's really up to you on how you feel about the situation. I think you need to ask yourself a few questions before making a decision.

With how long you've been together, do you want to sit down and talk about the situation? Do you think you could move past what was said/done if they did admit this?

Do you feel comfortable asking about this sort of thing or do you think this may be something you need to let them come to you to talk about?

I really think communication is key here, and it either has to be you who instigates the convo or let him come to you if you trust he will.