It seems as if your question was cut off, can you finish it so we can talk?
Are you going to leave this man?
What is your son going through?
Since your son is your main concern, I'm going to start out with him. He didn't ask to be brought into this world, right? But he is here now, and he's already had to deal with not having his own father, and now this new man, not just leaving but wreaking so much havoc in your life. What's to justify? Your son being exposed to mental, emotional and physical abuse? He should never have to see that, and by all means your 'husband' should be out flat on his behind. He's used you to get himself into a better financial position, and it's beyond me why you haven't had him charged. It would be some kind of miracle if he ever returns a cent of your money.
You have to do what's best for your son. You don't need a man in your life to raise your son. If you think he needs a man in his life, then talk to a male friend who you are not intimately involved with, like a grandfather, uncle, cousin, or find out if there's any type of big brother type program near where you live. If you meet a new man, do not let him near your son, not even to meet him until you've known him 12 months or longer. Sure it's going to be hard to move on with your life, but you will have to take it step by step by step, and it may be hard and there will be times when you feel like you can't go any further, but you will. You will because you have a son that depends on you and needs you to be the best that you can be. So if this means that you have no social life, that you go back to school, that you get a better job, then you do it. Show your son that he can be the best he can be by setting that example, show him that you're not a quitter and neither is he. Show him that anything is possible and there's nothing a little hard work won't cure. Show him that he's important by not allowing another man into his life until you have known them for a year or more and know that they're not going to jerk you around or take advantage of you. Meanwhile, its probably not a good idea to get seriously involved with anyone right now until you've had some counseling or therapy to find out why you are making the bad choices and decisions you are making. If you can't afford therapy, them maybe we can try to work through some things, it's up to you.
I think you're on the right track, you're thinking and talking it out. I'm not going to say whether what you feel for him is love or dependency, but I WILL tell you this...he doesn't love you. If he did he wouldn't do what he did to you. He saw you as a way to get back on his feet and he did that, all the while disrespecting you, your son, your family, and the sanctity of the wedding vows he took. Let him go before he causes more damage. Consider pressing charges if possible to try and get back some of what he's taken. Every step you take from this point on should be about your son...his feelings, his emotions, his physical and mental well being. Let your son know you have made mistakes, but this very day things are going to change for the better.
I welcome your thoughts, let me know if you want to talk more