Some will say it’s a guy thing, but that’s only an initial impulse, some of us guys do a better job of controlling our intial impulses or we are lucky enough not to be as easily turned around. OR we are not as sexually appealing to the opposite sex

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I think a guy makes a determination that he will or will not be open to such urges, sometimes as early as when they are dating or when they first get married. Some guys take their marriage vows dead seriously, no amount of temptation will ever deter them. Some probably don’t think much of it, they will be faithful IF no one tempting comes along. And some probably intend to remain faithful but are only half heartedly committed.
I guess you need to determine how important your marriage is to you and how important your marriage is to your husband. IF it is very important to both of you as it should be, then this floozie has to go and pronto and permanently, no last date, no last kiss, no more conversations if possible. The affair has to stop cold turkey. Your husband should have as little to do with her as possible, maybe even to the point of her or him switching jobs.
Then it’s up to you whether or not you can or even should forgive him. He needs to re-earn your trust, and you shouldn’t just have to take his word for it. He needs to prove it to you that he can be trusted again. Only a long time and continued faithful behavior can prove it. Personally, I don’t see how you can ever NOT be suspicious of him again.
For a while you will have to verify that what he says is true, when he goes somewhere or to some event, you may need to check that that is indeed the case. Maybe you can get one of the GPS phone and have him tracked 24/7, maybe get him a chastity belt. :whacky: It is a horrible situation to be in, but he has to regain the trust he destroyed by cheating, and that may be an impossible task…