WTBH - you've been missed here.
I have a bi-polar Mom; I can relate to your madness. Hang in there. I won't say it gets better...I think instead we get better at dealing with it all. But I can say that once a history has been established, these people have little credibility. And it doesn't take long for people to know something is "off". Your friends (who aren't friends any longer) will have karma come around to bite them, especially when your STBX does something irresponsible with their children in tow. You know its just a matter of time.
In the meantime, try as best as you can to detach from the madness. I know its hard - having had to do this for the last 20 years myself with my Mom, but its necessary, I'd even say crucial to maintaining our own sanity.
Prayers to you and your kids,
~T