It sucks big time to have a man that had responsibilities to check out in this way. It certainly burdens your ex in raising their children and a blow to your son in losing his step-father. Concentrate on helping your son get through this. And if you can, let the ex know it's in no way her fault.

My daughter's (middle child's) ex-husband pulled a similar stunt a couple years ago except it was an OD on alcohol. Alcoholism was in fact the reason for the divorce to begin with. Not that is does any good, I cannot forgive him. One of my granddaughters has to grow up w/o a father.