I'd like you to take a view of the big picture and reconsider some of your current attitude.
First, he's the WAS. You're the person trying to act in the reality-based manner, trying to behave in ways that reflect true personal growth, and true unconditional love - for self, children, and H.
Second, keep low expectations, especially regarding him and his family. Of course they'll toe the family line - their HIS blood relatives, not yours.
Third, don't A$$ume - anything. He's not necessarily acting in a vindictive manner. He's just a self-centered oaf - as are all WASs at most points in time, especially those going thru MLC patterns. For him, its not about you. Its about him.
Fourth, for you, its all about YOU. Not him, not the OW, not the ILs - just you, Hon. So get those plans in gear - get ready to be more financially self-sufficient, give your clothing/appearance some alterations that stop him in his tracks and set his blood a-boiling, reminding him how he looked at you in the first days of your R. But do so to remind you as well - that you have so much to offer this world, yourself, another person.
Every time I'm down about my XW or my sitch, if I take a look at my GAL work, I find that I've let things slip, thus allowing my PMA to slip in turn. Take a look there, and see what you can do to amp it up again, give it 1-2 wks and see where you're at then, okay?
The detachment is a good thing, Hope. But your attitude needs some adjusting, as it doesn't seem sustainable or sincere. Positivity/growth is lasting. The rest is destructive and self-defeating over time.