Sorry that you find yourself here. It will be a long and difficult process, so please don't think you will have to change things overnight.
What are you doing to "take care of you"? If you mean change your neglectful patterns and be a better man and father, great. If you mean focusing only on your needs, I think that's a mistake. Your selfish attention to your needs over your wife's got you here, so proceed with caution.
I would be surprised if there's not another man vying for her attention, especially given that you state that your relationship was generally good. Typically WASs that have met someone else will start to portray the entire marriage as having been bad, it helps sooth the guilt that they are feeling inside. Don't bother asking her, you won't get the truth if she is.
Can you give a more detailed description of your R along with a timeline of when you noticed a shift in your wife?
