There can be an illusion of total security for a man in a relationship that gets severely shattered when a child arrives. He can feel rejected and has a hard time coming to terms with this. New fathers who come to anger management have some hard lessons to learn Often they have been under the illusion that his wife is there to look after him. He loves the attention and affection she gives him. He is seeing the world as a child being looked after by his mother.
With a new child there has been lots of anticipation of how great it is going to be, and what a great job he has done in making this happen, etc, etc.(he had sex, big deal). The reality is the dynamics change as her affection is dramatically transferred to the child. Those bonding hormones of oxytocin take over and he becomes secondary. The baby is the focus and its needs dictate everything. The emotionally immature man cannot handle this goes into jealousy and depression that he is no longer the centre of attention.
To survive the man must move from being a taker to a giver. His energy and support are required to make the relationship work. If he is insecure and always looking for accolades of ego stroking he will be very unhappy. He probably moved into the relationship with serious co dependence needs and this first child is the challenge he has to deal with life on life’s terms or produce a child as needy as he is.