I am also still contemplating whether to investigate if the W is having an EA/PA.
What would change for you if she were in some kind of affair?
I can't predict exactly what impact it would have (beyond the emotion) and what I might do, but the possible big changes would be:
1. Financial: W has more assets and income due to stock options. If we part amicably (WAW instead of WW) I would say we each keep what is in our own accounts, I would not chase after any of her $$ (which is marital property). If she has been lying and cheating, I may be inclined to seek a 50/50 split, which may result in an extra $50K in my pocket and may impact my ability to keep the house.
2. Timeline: My overhead is going to go up by about $2500/month after D. Every month I delay I save that money. I might not be very agreeable to move things along is she has been cheating.
3. Living Arrangements: If she is having an A I would put the full court press on her immediately moving out.
4. Disclosure: I may expose the A, including to the W of the OM if he has one, as well as to our friends and family. I understand this may not be DBing but I would be looking hard at doing this.
5. Recon: Not sure if recon is possible for me if there is an A.
6. Overall Dynamic: the whole D dynamic changes if there is a verified A in my view. The story of the end of the M is completely different. How I would treat W would probably be much different. I will hurt more but might detach more quickly.
These are just some initial thoughts.
Thanks for the links R2C, looks like I have more homework!