It's time for you to have your Scarlett O'Hara moment - go look in the mirror, and with all the fortitude and determination, say, "As God as my witness, I will never endure this disrespect again!".
Then don't ask the inlaws, the OW or XH to change.
YOU change.
Take down the curtains - the illusions of the past. Make a dress out of those curtains - dust off that resume and change your circumstances.
Just because you might love what you do, or the job market might be tough, doesn't mean there's not something better out there you can do. Because there is. Because you won't have to see him every day. You won't have to relive this emotional pain every day.
If the job takes you to another community, so be it. The oldest is almost through high school. The youngest hasn't begun junior high yet. It will be a growing opportunity for all of you. Make your plans and don't tell a soul.
But teach your children about adapting and becoming stronger. Give them the tools and strength to say - Mom - if we need to move before I get to graduate with my friends, I will support you because I'm strong and want to make new friends anyway. I want to be a part of a new life.
Help them let go by you letting go.
I've been listening to an audio book/workshop on the way to work called "Fear Into Fire" and frankly fear is all about being resistant to change.
If you want your children to be courageous, teach them to embrace change.