Are there self-help groups for SI?
I have gone through periods of time where my self-destruction was taking the route of heavy drinking. And I have caused myself and others a lot of pain.
So I do not judge nor look at others as so very different just because the outward signs are different.
But bottom line is still: how much do you have to hurt yourself and others that you love before you say: "Enough! I cannot break free of this by myself. I need help."
The fact that you are posting is a good sign. It is a step toward finding a better way.
