A: They can both go to jail but it is not necessary. If your argument is self defense then you are probably going to have to go to trial and argue that your actions were justified. It will be for the judge or jury to determine if that was the case.
A: Contact the city prosecutor and explain the situation. If this doesn't work you need to contact an attorney who should be able to work out a deal to have your case dismissed. You may have to jump through some hoops to get there but it should happen.
A: It would depend on the severity of any injuries that you sustained. You need to contact a domestic abuse shelter and move to it with your children. He will not change and eventually you aor your children will be killed.