Leaving with my child?


I am living in New Bern, NC and have a 3 year old son. I ammarried to a very selfish man who cares nothing about anyone else but himself. Since I have had our son he has been better and has turned into a wonderful father but is a very emotional demeaning man as a husband. I have been unhappy for a long time and have recently considered leaving him and taking my son with me. My family is about an hour and a half away in Wilmington but I dont want to take him from his father I want him to be able to see him when ever he would like. I have a full time job and make just about as much as he does but I know I cant support myself and my son and pay for the house we have built together.
I have a friend that I work with and he has offered to allow me and my son to stay in his home. He is currently going thru a seperation and the papers are on their way to being filed. My son likes him and we have all been friends for over a year now.
I am worried about the ramifications of taking my son and leaving but the fact that I want to leave and still stay in the same town should be a plus I am just not so sure he will see it that way. I also dont want anything legally to happen to my friend at work.
I take care of my son in all aspects. I dress him, feed him, drop him off and pick him up from school. I do everything to be a good mom I am just tired of feel underappreciated and talked down to. I have several witnesses to his verbal nastiness towards me and I also have written testimony from him to me saying he feels no passion or love for me and that he would never go seek counseling together.
I need to know what I need to do. He knows I am unhappy he doesnt know I am thinking of leaving.