回複：there are several states, but I will just give up

You are right. I looked it up and there are some states still apply common law marriage rules. However, to qualify as a common law marriage, you must have strong evidence such as filing tax together. Just simply living together may not be enough. Even if there is a common law marriage, it is the man you live with who committed the crime, not you. Adultery may be another crime, however, it is rarely prosecuted. Your child born out of wedlock should also be legitmate so that you can require child support upon separation. What you need to do is to ask the court to declair the marriage is null, then hire a lawyer to fight for child support.