In our case I did tell wife , expected worse but she was more than ok with it.
Personally, I'm happy to see that you didn't shy away from it; when my step-son turned 20, he had girl problems that led to us being lovers for a couple of years and I didn't hesitate even though, later, his mom found out and got on my case because he told her but I didn't. Otherwise, it was damned good while it lasted.
Definitely wasn't planned. Just kinda happened.
Not many guys would have done that, let alone admit to it...
