It sounds like your wife might be struggling with the reality of having a special needs kid. I know it can be rough on a marriage. Have you ever sought counseling for that issue?
Also, if both of you have successful careers, could you hire some help to reduce stress in other areas to give both of you more mental and emotional resources to deal with your son?
Me: 44 H: 44 Kids: 20, 16, 16, and 10 Together/Married: 22 years H announced he was emotionally detached and considering D: 4/4/16 H announced he is going to try to stay and reconnect: 5/1/16