You are going through the stages of grief. Anger is one of the stages and the anger you have will help motivate you to move forward. Be careful that you do not take this anger out on her. If you must do something constructive w/the anger, then find a hobby or project that you need to complete. For example, shoveling snow would be one way to release the anger. I'm sure you have other ways to release it if you think long and hard.
You are trying to rationalize what she says and/or does. Unfortunately, you can't, especially when she's in an emotional state. Her big secret may not even be the affair, it could very well be something from her past, i.e., drug/alcohol use, rape, abuse, etc. We just don't know what transpired. But, I honestly don't think it's the affair.
As for her not being attracted to you for the last 3 years, that's typical mlc lingo. They all tell us that bs and the years change like their moods. Remorse is fluff to them right now. Their empathy chip is broken and it will take some time for her to show genuine remorse, if ever.
Keep in mind, the "I want to be happy" is another comment out of the MLC lingo book. Happy to her may not mean the same thing as happy does to you.
Let her comments go, try not to over analyze everything she says and does or you will drive yourself insane. The holidays, the weather and being ill have gotten you down and you are sitting in the rabbit hole. The first order of business is rest and drinking plenty of fluids. You have to take care of yourself or you'll end up in the hospital.
The old saying around here is "let go, let God" and that is one of the wisest sayings we have. Keep the focus on you.
Sit quietly, the answers will reveal themselves when you least expect them to. The past is gone, the present is a gift and you need to focus on today, allow the future to reveal itself when it is ready.
