Many times women are intoxicated by a mans attention, they are swept off their feet. All that means is that these women are not grounded, they do not have their feet planted firmly on the ground. Added to that alcoholics/addicts have an uncanny ability to read women, and entice those who are needy and vulnerable.
So, finding a woman is easy, keeping one is another story!
You are awfulizing and projecting into the future, your ex may live to be 70, there is no way to know.
Enjoy your life and your children, let him go. All this thinking about him is unhealthy for you, your peace of mind.