What Stormbride said.
Please consider leaving before the end of the month. Call your local DV shelter and let them know what your situation is.
It takes so much strength to do what you are doing. Do be careful who you share your story with IRL. The last thing you need is judgement. You are trying to do what you feel is best for yourself and your DS, even for your husband. By leaving you can keep yourself and DS safe, as well as hope that your husband is able to find help and a way to live a happy life that he doesn't have, that none of you have, right now.