Upon further reading, it became clear to me that you are not talking about a minor child. Your husband is smart enough to know that you cannot force an adult to do something against his will and expect positive results. It is clear that you are suffering the pain of shame.But that does not even come close to what your son is suffering.It is clear that your son is not fully financially independent.Sure, you can take away his car and even throw him out of the house, as you say.When he understands your fears and vulnerability, he may open up to you and tell you what is really going on in his life.It might be that your son just needs some time to find himself, and he will then be ready for marriage. Prepare yourself for the possibility that he might disclose a serious or shocking motive for not feeling up to getting married.Knowing that he cannot do anything to change the way he feels about getting married, he will do whatever he can to convince you not to make good on your threats.
Raising children is not like connecting the dots on a picture to get a perfect result.
The reasons are endless, as I am sure you have heard.
There is a myth amongst some families that when a child refuses to get married for a specific reason and you nonetheless force it, he or she will magically be happy and live the life that is acceptable in their community.
Stress how much you love him, and apologize—yes, apologize—for the way you have been treating him.
Allow him to see and understand that you have been acting poorly to him because you felt susceptible to the gossip surrounding you.