Wow. I hardly know what to say. I am so sorry about your sitch. I think you're doing the best you can under the circumstances and, as you say, you can take some comfort in the fact that at least it is all out in the open now (which will make it easier for you to deal with than the denial and deceit).
Apart from abuse (physical, emotional, substance), sexual orientation is the only other thing I can think of that makes saving a marriage nearly impossible. As a result, I think you are wise to begin preparing yourself for its inevitable demise. That doesn't mean, however, that there is absolutely no hope. If your WAW's "impulses" are being driven by unaddressed issues from her childhood, then if she chooses to address those issues, her interest in women may prove to be an adaptation or coping mechanism rather than a lifelong change. However, it is just as likely this will not be the case. The best you can probably do at this point is to place it all in God's hands and maintain a civil relationship (which it sounds like you've already done) at this point.
I can understand if you feel it's time to move on from this community. But you may find you still need some support. If so, I'd encourage you to start a thread in the "Surviving the Big D" section. If you decide to do so, let me know. I'd like to keep up with how you're doing.