Originally Posted by
Duped 
It's their own ego that causes it for a large part, I believe.
Imagine being in your 30's or 40's and having little to nothing to show for your existence on this planet, and that your only accomplishments have been to ostracize your friends and push your loving family out of your life, to the point that they want nothing to do with you anymore.
It's all ego. Addiction is a disease of the ego. Though I can say, I don't think anyone actually wants this for their life.
I think they are confused about why they do what they do.
They self sabatoge to prove to themselves even more than they are not worthy.