I don't know what you have done with her previously, but consider this. Become an "open book" to her. Make sure she has all your email account passwords, access to your cell phone and any other device that you use. If the other woman contacts you, tell your wife. Be completely honest with her. Answer any question she poses as honestly as possible.
It is up to you to make her feel safe with you again.
If you are the grabby, touchy, feely type, then try being more manly and confident. If you are too much the manly type, then learn how to be more sensitive. Whatever you do, strive toward re-instilling trust in your wife. Be there for her, be her hero.
If you tell her she is beautiful right now, she probably doesn't believe it. Same thing with sexy. My guess is that she is doing you in order to feel good about herself - doing the right thing. You need to recognize and appreciate her efforts. ACKNOWLEDGE HER CONTRIBUTION TO THE MARRIAGE.
In short, you have to learn to be a good husband, and in short order. You must do this for a good while before you can get back to the sex issue. At some point in time, both of you have to address conditions in your marriage that contributed to the affair. Make sure that you completely understand that it is NOT YOUR WIFES FAULT that you had an affair.
These are all probably points that you have heard before. I am trying to help with your SSM, but you have to address the affair fallout as FIRST step.
All the best, -NOPkins-
I will ferret out an affair at any opportunity.
-An affair is the embodiment of entitlement, fueled by resentment and lack of respect. -An infidel will remain unreachable so long as their sense of entitlement exceeds their ability to reason.