Stop Paying Child Support Without A Judges Order

(Nv.)

We live in Las Vegas, Nevada and have been divorced 3 yrs now. I have joint physical custody of our now 16 yr old son and receive child support. This past year my son has spent more time living with his dad, my ex than here with me. He likes going back and forth to both our houses but when it comes to enforcing good grades at school and curfews he wants to stay with the ex...August 28th then again August 30th I asked him about the support check for August, he never responded.

Sept 2nd I received a check in the mail for half the normal amount (only the spousal support portion) and immediately called him, that's when he said he's not paying any more because son is there. I told him he can't just stop following a judgment from the court or an order on his own and he said his lawyer said he could. This can't be correct can it?

Now I've received a letter from his attorney stating he's taking me to court and now wants full time physical custody and me to pay him support. Is there anything I can do about this, he knows I can't afford attorney fees and I just leased a house for a year with the intent of having child support as income to cover the rent. I don't want my son there full time for the fact there is no supervision after 8pm...that drives me crazy. Well I guess what I'm asking about is..

Can you stop paying child support on your own or if advised by an attorney? Can my 16yr old request in court to live with his dad and is that usually what judges will favor? Even if my son prefers to live with the ex can the judge still say that its in his best interest to stay with me?

Is it possible or likely I would have to pay child support even with the large income difference his being 3 times mine? Are there ways to afford legal help so I don't have to basically represent myself?

Thank you, much appreciated.