My suggestion is that you do not contact your W. Do not tell her to date OP.
Listen, you are not in an emotionally strong place to be making big decisions. You are "reacting" to things.
For example, you first are shocked that anyone would even mention the idea of dating. Not when they were still M!! You couldn't do that! But, after a couple of replies.....you're on the Internet connecting with a woman from h.s.! What the heck? Now you're ready to tell your W that she has your permission to date?? Why, b/c the girl from h.s. was nice and your ego is soaring?
Just try to settle down and leave things along for a few days, okay? Your W doesn't need you to tell her anything about what you're doing or that you don't care if she dates. Why should she? She's pretty much doing what she wants, right?
Now, let me tell you a little secret about women. They KNOW when you want them to THINK you are dating and having some big life.....that you really aren't. So, don't even go that route.
Your emotions are extreme right now. You may feel completely different next week.
It is not about what you feel should work in your M. It is about doing the work that gets the right results. Do what works!