@ce2022,
When you have physical custody of your children, why would you pay child support to your wife? It is her who should have paid you. Child support ends
either when the kids are 21 years old or finished with their education.
Your children are adults and over the age of 30 - no child support needed and if you paid child support to you ex wife for all these years, at least your children should have had the decency and told you to stop.
By all means go ahead and stop immediately. Actually, you could ask for a refund, but I doubt they would pay you back.
You are a good man, but don't be a sucker now!