The good news is that a 90 year old man in a wheel chair is only so much danger to a grown woman.  Inappropriate on his part and embarrassing all around, but its life. I've known several people that received calls from nursing homes about elderly "misbehavior". 

As far as anyone knows, he was always a man of good character in this regard.  When the mind goes and inhibitions fade, things happen.  People live a long time now, I hope if I get to this point I don't embarrass myself or others too much.