Hello Nella, and a warm welcome to the forums.
I am not here to judge you on the affairs that you've had but try and help through this rather difficult situation, but perhaps counselling may have been a better idea for yourself, rather trying to rely on another person who had an intention on something else.
With your husband being defensive and also angry closes the door to any communication between the two of you, that's exactly what you didn't want, so you tried to find other people who could support you one way or another.
The rejection by this other person may not have been interested in what you wanted to say, so, unfortunately, you were let down once again, so what has happened is only caused by circumstantial circumstances, it doesn't mean you don't love your 8 year old son, it's only been hidden by what you've had to experience, this can be recovered by talking with your doctor, to begin with, and then referred onto a psychologist.
Whether or not you decide to leave your marriage is whether your husband seeks the help he may also need, but your son needs your affection and that's what you should hold onto.
Please post back when you have the available time.