Even if you CAN avoid testifying, I feel testifying could help with your custody regarding the divorce.
It certainly couldn't HURT that case, and in my opinion that's the more important one - kids who are stuck in the middle through no fault of their own trumps an AH trying to avoid the consequences of his own choices ANY DAY, in my book.
I'm sure you could use the results of this case, whatever they are, in your divorce proceedings.
In that case, it stands to reason that it would be more helpful to have as much accurate information as possible in this case, not because of this case, but because of the NEXT one.
Just a thought.
When you testify, maybe just remind yourself that you're doing it for your kids?
You've done more than enough for your AH.
There's only one more "gift" you can give to him, anyway - the gift of experiencing the consequences of his own choices and actions.
The gift of being completely responsible for himself.
And that is a gift.
It's all about what you do with it that determines how well it treats you.
You're starting to take responsibility for YOURSELF, and you have been making great changes.
Now it's his turn, and he can do with that freedom and responsibility for himself as he sees fit.