There are many here that understand your confusion and fear about leaving your SO. We have been in your shoes. I left my kid's dad when they were less than two years old and I know that I made the right decision, as hard as it was to do at the time. It was hell, I will not kid you about that. But I was living in hell with him and I know that if I had not left when I did, I would have been dead. I did not want strangers raising my children, they needed me, and that thought made me gather my strength and do what I had to do.
Have you contacted a women's shelter in the area to give you counseling and advice? It might help you see what you can do for yourself and your son. They might be able to answer questions that you have about custody of your son or refer you to a lawyer who can help with advice. Be proactive and do this now while you are deciding what to do. You need to know your options.
Don't tell the SO that you are thinking of leaving. It can get very scary if they think that you will actually leave. The violence, both physical and mental that they can/will do to you and your son, can be unimaginable. This is just a caution. This can be the most dangerous time for you if he thinks you really may leave. He sounds like he must be in complete control to maintain his masculinity. In actuality he is a coward, threatening and treating you like he has.
Addictive personalities can be very difficult to live with as they do not see that there are problems, the problems are always directed at you, no matter what you do, act, say, nothing you do is ever perfect enough for them even if one time it was okay, this time it throws them into a rage.
I left with a few things packed, some important papers, like birth certificates, etc., very little money, no job, no place to live, and moved as far away as I could. The kids and I lived in the car for awhile until I got on my feet.
I know that you are worried that he might take your son and that he threatens that you would never get custody back. If you have no drug/alcohol problem, and that can be proved with blood tests, have realtively stable employment or educational history, no rap sheet, (arrests, etc.) and no history of psychological problems, you are in a much better position to retain custody of your son than he is.
I had Child and Family Services called on me numerous times even after I moved far from him. He was just harrassing me and messing with my mind. All of the allegations were unfounded, and the Social Workers knew the situation. It is very common to have pissed off ex-SO's try to get you back with these tactics. Hopefully the folks at the women's shelter caould give you some information about this phenomonon.
You have to decide if you have strength to stay or the strength to leave and that is tough call. He really does not love either you or your son by his actions. You deserve so much more.
