You know what? For a second, let's take you out of the equation. Not that you aren't key in all of this, but I know that when so much has already happened and with all the history in your relationship, it's sometimes easier to think about the other people involved in this. So here goes:
1. Your son. Family violence is generational. Do you really want to wait around until your husband has a chance to abuse your son emotionally or physically too?
2. Even more--do you want your son to grow up thinking that this is how men treat women? Do you want to be the mother of a wife-beater?
3. Your husband. It's terrible that he was abused as a child. No kid should go through that. But we are all accountable for who we are as adults. If he were an alcoholic, he'd still have to make the choice to stop drinking. What has he done to stop abusing?
4. For the record, I worked in a family violence agency for about 4 years. It's not common to see men go to jail. Probation, yes. Offenders counseling, yes. Jail was pretty rare. If your husband spent more than a night or a weekend in jail, he must have either quite a history in the system, or have done something pretty serious to you. Please, please, please take it as serious as the D.A. and police did.
There are so many options and paths you can take right now. Feel free to PM me if you want some ideas for resources that could be available. If you haven't been in contact with the Victim services office in your county or your local domestic violence agency, they are a great place to start no matter what your plans for the future are. If you don't know where or how to contact the agency in your area, you can call the national domestic violence hotline at 1-800-799-7233 or visit their website at National Domestic Violence Hotline
to get a referral to the agency and resources in your area.
Any way you go, it's a good idea to think for the future to plan for ways to make sure you and your son can be safe when things escalate with your husband again. That's the most important thing.