I'm going to vote for ignore.
The "wanted to make sure you were ok" thing is indicative of a severe personality disorder, and not a good sign.
(Wtf is it even her problem if he is ok? If he had been hit by a car and was in the hospital you'd be the one taking care of him anyway.)
If you give her anyyyything, she will continue. If she reaches out to you 10 times and you finally lose it and shriek "leave us alone" she will understand that all she has to do is harass you 10 times to get you to respond.
At this point she has closure. The wife has found out, her married man is gone, the affair is over. Tale as old as time.
Personally I say block every way for her to contact you, if you get a call from an unusual number, don't answer, she might try calling you from one of her friend's phones. And there are ways to verify that and then you can block those numbers too.