If your mother married a citizen, then she will have a conditional greencard for two years. After that she will get the permanent one ( an if she likes that's when she can file a divorce and not worry about losing his immigration status). Once she gets the conditional greencard, you should also get one if you are under 21. Then you can get a SS number and other documents. During this time you will be able to aply for financial aid ( you will also be eligible to pay in-state). Once you get the conditional greencard you can also join the military. You can also start working for another institution that will be able to sponsor you and, therefore get you a permanent greencard without you having to worry about your mother's immigration status. You don't have to contemplate suicide. if you want to keep studying , you can go to a community college for the first two years and then to a 4-yaer insitution ( once you either got your greencard or saved enough money). Finally, renew your brazilian passport , go there , and get yourself some brazilian ass.
Regards
ng