You can file a lawsuit even though you have no legal immigration status. However, if you file a claim for lost wages, past and future, you immigration status will come up as the defense will most likely argue you had no legal right to work. Make sure when you obtain an attorney for your personal injury claim that he consults with an immigration attorney. I have consulted on many such cases in my jurisdiction.
An annulment is a legal theory by which the court treat the parties as if the marriage never occurred. Every state has a different basis on which to annul a marriage. But with annulment you are unlikely to get any spousal support. As for the green card, if you believe the marriage was a fraud, you can report that to immigration. In either case, you need a attorney who does both family law and immigration.
Other proofs: pictures of inside of home showing both your belongings, mail addressed to both of you at same address, sworn affidavits of neighbors or friends who know you live together, and other bills you both have in both names that come to that address.
I would strongly advise consulting with an immigration attorney in person. Those "withheld crossing" may be what is referred to as "expedited removal" in which case re-entering afterwards could lead to a 20 year or even permanent bar to admission. I would suggest at the very least, hire an attorney to do what is called a FOIA request to get all the information immigration and border patrol has on your husband.
Only criminal defendants are entitled to public defenders. You will have to pay an attorney yourself. What is costs depends on location, issue and expertise. You should call some immigration attorneys in your area.
You mother can file and I130 for you to sponsor you for a green card, but you will have several years to wait. However, consult an attorney,as under certain conditions you could have received derivative citizenship through your mother.
There are special requirements if you missed the one year filing deadline. You really need an immigration attorney who handles asylum and deportation as you will have an individual hearing on the merits of your asylum application.