Hi TinaP and welcome to PsychCentral.

Have you considered family therapy with all four of you? It sounds like there are so many strained dynamics, that working with one professional who sees the whole family picture would be really helpful. The family therapist could work with all of you together and also subsets of your family too, sometimes just your husband and you, sometimes a parent and child, etc.

I was confused by the car situation. Your husband is already paying you child support, which you are using to make car payments? So you are already well on your way to divorce if you are receiving child support? I think you have been more than generous with cars for your son. He is 18 now. Maybe it is time he was responsible for providing his own transportation, saving up money from a job to buy a car, etc. Because it sounds like this car thing is causing big problems in your family, and if you take that off the table, and let your 18 year old adult son have that responsibility, perhaps it would help things all around.