IMO, the problem may not be the kid as much as your lingering sense of inadequacy. Your wife choose that man - ouch. Then, at some level, you come to believe his sperm is also a better choice - that is rough.
You feel that he is the better man and that "truth" lives in your house.
My words may not be what you want to hear but I ask you to step back. In what way is this AP superior to you? He lacks character, he lacks morals, and he takes what he wants. Are these traits to be admired?
AP is not your son's father YOU are. Who gives your son room to grow? Who teaches your son what it is to be a man? Who is the one living a moral life?
I would tell the boy - out of love not anger. You choose him. Celebrate what a good man you are and the man your son will become.
The healthiest plant in the world will die without water and light. Take revenge on the AP by raising a powerful and loving son.
