Frank,
Some of the relational aspects of your sitch are very similar to mine. I suffered from mild depression periods over the past 5 years (not on anti-depressants though) and WAW was not assertive in knowing how to help me so we both spiraled down a vortex of hurt and resentment. This, together with my critical, controlling nature eventually led her to pull away from me since her emotional needs weren't being met. She in turn sought out the comforting, consoling, support and sinister nature of OM/BIL who was more than happy to take her away.

But there are two big hurdles. The affair and whether or not I can forgive her for what she did (I can't right now) and her fears, and whether she can forgive ME for my mistakes and believe that I will not be that person ever again.

Ditto. Even though WAW said she saw changes in me over the past year she resented those changes and even resented me. "Why am I so worth it NOW," was her mantra until she left.

How can we get over those 2 hurdles? Not totally sure how/when it will happen, but obviously MUTUAL FORGIVENESS is the key. Since I'm only responsible for myself and controlling my own behavior, I must forgive WAW for the devastation she's caused. Easier said than done.