what to do

If what you say is the honest truth, it sounds like your wife is stuck in a fantasy land where "the truth according to [her name] is more important to her than reality is." One of the interesting traits my STBX has, by the way.

You can't do anything to make your wife understand, much less get over it. She has to be willing to understand. Your part in it is limited to making sure she knows the realities of the affair, including how your feelings when you got into it, were participating in it, and ended it.

There must have been something that made you interested in getting that first blow job. Do you know what it is/was? Does your wife? Has it been dealt with by both of you so you can be sure you won't be tempted again?

I suspect some or all of that hasn't happened. And there is no reason for her to "get over it" until it does. She has to know why you had the affair, and know that those reasons no longer exist, before she can trust you to not do it again. And she's not going to get over it until she has that trust.

On the other hand, if she now understands what went on and has no reason to think you will do a repeat, something is wrong with her feelings about/for you.

Either way, it seems you two don't communicate well enough to get her back into the place where she trusts you won't do it again. So my suggestion is to get some counseling. Go over the motivations for the affair and their elimination. Or go over why that hasn't put her back in the place of trust. Whichever is appropriate.

Good luck.