May I suggest something different?

A perspective change. Speaking just for me, I have control over no one but me.
I think that people sometimes cheat. Even people who are in love. I am as vulnerable as you are to those fears. But I have decided to accept that if that were to happen. If my husband were to cheat. I will see it as his lack of integrity.
I will decide what I will do if that happens. It is not about me but it will require a decision on my part. I have told him what I will do and that is all I can control.

I be
May leave or may not. I will however lose respect for him and things will never be the same. In the meantime enjoy. Hoping always for the best. Ask him to show you by being transparent.

I wish you all the happiness you deserve.