Hello 3kids. I'm sorry you're in this and that your weekend with your kids didn;t workout as you hoped.
I read about your asking your W to do things with you. I do have some advice that works for me. Make a specific and definite plan to do something on your own or with some friends... like going out to lunch or going out for coffee. Then, you say to W... "Hey, I'm going out for (dinner/lunch/coffee/drinks) (now/at 7pm/at noon) (with bob/mom/kids if someone else is coming with you). Care to join (me/us)?
Then, if she says no, warmly (with no disappointment in your face) say "OK" and then... most importantly... go anyway.
If she does go... only have light conversation. Do not under any circumstances talk about your M or R.
Then, make the time together short and end the time together yourself. Plan something specific and real to do next so you can excuse yourself. "Hey I'd love to stay longer, but I have to (meet/do/go) (somewhere/someone) at (time). I'll see you later."
That way... she starts enjoying no-pressure time with you. You are providing fun and happy memories of you for her.
Have no expectation when you ask. Have no expectations when she goes with you. Have no expectations during the time you spent together. And, most important, have no expectations for (hugs/kisses/next meeting) when you leave. Her her lead on all those things.
This works.
Me: 44 W: 45 S: 11 Married: 15 Together: 18 BD: 9/29/2014 OM discovered: 10/16/2014 I left her behind: 12/14/2014