This girl is as much in the wrong as your partner as she knew about you, doesn;t matter wether she knew about the pregancy or not, and it doesn;t sound like she found out about you then admitted everything because she wouldn't turn nasty to you, i believe that she is being horrible to you beause he has rejected her, and i would take what she says with a pinch of salt, I would also take what he says with a pinch of salt too, i would definately agree to the couples counselling even if you dont get back together you can at least look your son in hte eye and say we tried everything, because to me you dont sound like you are ready to walk away so the counselling i think will help you with confidence aswell if you need that extra confidence to make it work, or extra confidence to be strong and say stay away for good just see the kids.