You should expect nothing less from his family. Of course he has told all of them just that - "Now she is trying to have me thrown in jail." Conveniently leaving out of course that he has continually failed to support his children financially and to give to you the support ordered by court.
I still think fondly of some of my ex in-laws. But I have a relationship with none of them. It is simply a very difficult thing to manage. They cannot help but support their own blood, and eventually that means that they must reject us.
You have grown emotionally, spiritually, and become a strong woman and mother. Do not allow the misguided thoughts of some to throw you off kilter. They have not walked in your shoes, and they may not even see the sickness and madness that their family member is still walking in.
Focus on the good in your life. Your own family is strong and loves and cares for you and the children. They are your rock right now and they will see that you are not left alone or wanting.
Allow your ex meanwhile to travel this road of deceit and manipulation. Though it sometimes takes time, I am still convinced that such a life eventually is shown for just what it is.
Blessings,
Bill
"Don't tell me the sky is the limit when there are footprints on the moon."