Drinkmoretea, I saw your post and had to reply. You're talking about another taboo subject here, the dislike if not actual hatred of one's own child.
I've had experience of this myself. Though while you seem sure it's your DS's behaviour, I could feel in myself a creeping loathing for my son, and as much as I hated myself for it I couldn't seem to help it. I tried to hide it and in fact, he was indulged, as far as clubs and activities were concerned, more than his sisters. But sometimes, perhaps triggered by his 'lip', which is only natural from a child, I would feel an irrational inner anger towards him that I don't remember feeling towards any of my other children.
My son was the only boy with several sisters and was a similar age to yours when I started to take a dislike and, yes, even hate him. It was a long time ago so my memory is a bit hazy as to why this came about - it could have been his behaviour, though he wasn't particularly difficult, a bit lippy but not in trouble at school or the law or anything. I was a young single mother under lots of stress, struggling with money, all the usual stuff, though we were lucky to live in a wonderful place in the country with lots of space - no grotty, rundown inner city council estate or anything like that to blame.
I cannot say, definitively, what caused it. I loved all my children as passionately as any mother, including my son until he was about nine or ten when this happened, and I cannot even be sure my relationship with him ever fully recovered, given the the onset of the stroppy teens which changes things anyway. I don't even know if he realised himself, my feelings towards him at that time - I hope not. But even now we have a volatile relationship, and often don't get on, so perhaps it did have a deleterious effect.
It's rarely talked about but I'll bet more mothers have gone through this than would dare to admit, given that it's regarded as shameful, perverse and 'unnatural' - which is why I've changed my name for this post; I still feel shame for it though my son is now in his thirties. I applaud you for voicing this, when I am too cowardly and have never spoken of it. I don't even know if my experience is the same thing as yours but it happens and it should be aired.
What I would say though, is I wish to god I'd done something, got some advice, help, talked about it to someone - something. I would do anything to turn back that clock. I am proud of my son, I do love him, he is my son - a fine, big strapping chap. But I bitterly regret we're not close and I strongly believe that it's all my fault - I was the adult, young as I was.
I know I might sound melodramatic, but it's too late for me now, but not for you. Clearly, you have to change something, fix those fences before he grows away from you, as they naturally do in teenhood, before it's too late.