And her acting like nothing had happened the next time she say you, was the correct response on her part.
Yeah, I think Donny’s wife did that (was a bit effusive) because she remembered the last time they saw each other there had been an awkward scene. She wanted to make sure everything was ‘okay’.
Or, she's twisted, and got off on the drama and confusion that her gaslighting caused. Acting like nothing happened is her little "victory dance." Given her current circumstance and history (beautiful woman on 3rd drama filled marriage, cringing husband, gaslighting acquaintances) I'd say OP is in for more of her game playing unless she steers clear.
Seriously, once you meet this type of person, you never forget and can spot them a mile away. Posters who've said as much are well aware too. Sorry to harp on this OP but there is danger in getting closer to a warped person like this. If she's not this type of flawed, I'll eat my hat.
Only way to tell is further experience, unfortunately. Good luck and polite observation! Report back please