N.H.
You can make him leave and you should. If anyone called my kid names I'd have a hard time not ripping their throat out. You will likely have to sell the house if it is in both of your names. Selling before it destroys your credit rating, especially if you are the primary borrower is important. I would advise you to call legal aide in your area for representation. Much like in a divorce situation you should be able to get a temporary relief order in place requiring him to leave and possibly continuing to contribute financially while you resolve the housing matter. I'm guessing you are paying far too much for a mortgage payment and selling and going back to renting will free up some money for you and possibly allow you to get a car.
I would really advise you not to leave the house though, unless you feel it is unsafe for you and your child to be there. If you leave, you may forfeit your right to come back and he could stop making mortgage payments and live there free of charge until the bank forecloses. I hate to say this, but that might be an option for you to consider, stopping payments and letting it go into foreclosure would probably give you about six months or possibly as much as a year of free rent while saving the money to start a new life. If you are already behind on payments, owe more than the house is worth - I know good people who've had to make those choices.
As for concerns about your son having special needs, the best thing you can do is move forward with testing, diagnosis and treatment. I promise you this will be beneficial to you and your son long term and long term is how you need to think as a parent. You really do need to ask yourself if the decisions you're making now will be good in a year, in five, in ten - for both you and your son. Your local public school district will have numbers for you on early intervention services. If you do not have transportation - they will often come to your home or line up a means for you to get yourself and your son to appointments.
Act now, this is your life and it's important.
Legal Aid of Milwaukee - ###-###-####
St. Francis Children Center - ###-###-#### (Early Intervention Services in Milwaukee)