Thanks for the updates on your situation. Glad to hear you had a great time at the wine festival and were with some new friends. WE really must use this time to grow as people, and not just by reading! Getting out to new activities and with new people is wonderful.
I wish I had some sage advice on the kids and OM, and and the IL. Do the ILs try to defend your wife when the kids are around? Do the ILs bad-mouth you to your kids? If so, I'd keep them away if I were in your shoes. I don't have kids, however, so my advice may not be worth much. If they don't do either of those things, then maybe preserving the relationship with the grandparents, if it was "healthy" before your separation/divorce, may be a good thing. How do your kids feel about your ILs? Have those feelings changed since your separation?
You sound like you are in a pretty good place emotionally, and I'm glad to hear that.
I read Peter O'Connor's book over the weekend, and he talks powerfully about mid-life as a time for men to look inward after spending much of our lives looking outward at jobs, etc. He contends that if we men accept the challenge of introspection, even though that is painful at times, we will grow and our midlife will be a time of creating a "whole" person. He borrows heavily from Jung, but he makes a lot of sense in tying MLC to unresolved childhood issues that we LBS can do little, or nothing, about. So, I applaud you for your healthy attitude and the work you are doing on yourself. Keep it up, and take care of yourself and the kids. Don't forget to give some joy to others each day.
