Alcohol can def mess people up. My mom was an alcoholic. She would give me haircuts when I was like 10. Her hands shook so much she kept stabbing me in the head with the scissors, and blaming me. "Well if you'd hold still!"
Thankfully she never put out one of my eyes! But I bet if she had, the shock would have been so great she would have joined AA right then and there, instead of 15 years later after my father divorced her.
The thing is, on the whole she was a pretty good mother.