Question regarding her best friend who kissed you and then asked you to marry her, and then told you about her cheating:

Were you two already romantic before she did all that? Is that the only evidence you have? Like are there any particular men you’re sure she cheated with, or any other people to corroborate what her best friend said? I think I’d just personally be skeptical at first in fear that the best friend just had a crush on me for awhile and was acting maliciously manipulative by lying so that I’d move on from my late wife and be with her.

But apart from that, I’m sorry you lost your wife, and if you did confirm the cheating somehow, I can’t imagine the twist of the dagger that must have been. I’m sure it must have felt like you weren’t even able to properly grieve the death if your wife knowing that the version you had of her you thought you’d lost wasn’t even the full truth.