Divorced and pay child support, health insurance. Son just turned 18. when do I legally stop paying for his health insr? in Dallas Tx.?

That should be cited in your original court order. Some child support arrangements end at 18, others carry through college. 

your child is not the POS....even if there are issues....you brought him into the world, you have a moral obligation to provide for him until he can provide for himself.

when the court says.  why are your bragging about wanting to be a deadbeat and not a father?  you really want him un insured and to die?  CHILD SUPPORT LAWS VARY, in some states, it continues while child is still in school full time.  even if it is no longer required, the DECENT thing  to do is pay for it for up to a year (depending on exact circumstances..maybe only a few months) so the kid has time to look for a job/get an obamacare plan himself.

assuming child support is ending....you should give him an allowance until he has a chance to get a full time job and have pay checks coming in....at least 1 month after high school graduation.

Sorry you ran into a golddigging POS. 

Look at the child support order.  You can carry him until he is 26 I think.  I mean, you may legally be able to drop hi now, if you want to be a horrible person.

Unlike the poster who referred to 26 is false, that is an option that a parent can take if they want to provide continuing insurance benefit; it is an option for the parent, not required under any law. Others have correctly pointed out ends at 18 or upon HS graduation. Need to go back to court to get clarification. 

In Texas child support is due until the child turns 18 OR when the child graduates high school, which ever comes LAST.

the left under Obamacare says, you have to cover him until he's 26. don'tcha just love those liberals?

That depends on the divorce order says. Typically child support ends at 18 however sometime it does not end until the child graduates HS or even college.

Does the court order have an end date written into it?  If not, you probably have to go back to court to get the order changed.

As long as that order is in force, you have to obey it.  A change in circumstances (the child is an adult now) is sufficient reason to go back to court and request termination of your support obligations.

But I don't know Texas law specifically, so maybe there is some law that terminates a support order without requiring a hearing.  I doubt it very much, but maybe.