Well, I can't say that I've ever heard reference to a weak soul as the cause. Now if you want to talk about a 'hole in the soul', I can speak from experience.
I think I was born an alcoholic. I never ever felt like I fit in anywhere, even as a child. I had this sensation of never being comfortable in my own skin. There was a big empty spot in my soul where the cold winds blew, and the solution that I discovered was chemical in nature. I was raised in a good middle class family, albeit now looking back, there were a lot of dsyfunctional and rigid attitudes that carried over from generations of alcoholism on both sides of the family.
I didn't want for anything material, though my family lived on a budget and I didn't always get what I wanted, but always what I needed.
I attended church and catechism on a regular basis, was an organist at church for 5 years.
My parents always told me they loved me before I'd go to bed at night and give me a hug and a kiss.
We did family things on a regular basis.
Why wasn't that enough for me?
I don't know. I just know something was missing inside.
I also qualify as a codependent, having been married to an alkie/addict who was buried last year at the tender age of 47.
I also have two alcoholic daughters, the youngest who just wrecked her car badly this past weekend.
I love them both, but I don't have to approve of their choices.
They've both been raised around recovery, and still chose a path I wished neither one ever would.
Why did they choose that path?
I don't know. The why isn't important to me; it's what am I going to do with this moment in front of me that is.
Today I have a full and reasonably happy life in spite of having two alcoholic daughters.
I just started college classes today and am going for a double degree.
I have found for me, especially in my codependency issues, that I wasn't nearly as angry at the alcoholic as I was at myself for putting myself in a position to be hurt in the first place.
Forgiveness of self has been one of the most difficult things I've ever had to do, but it was so worth it.