I know this is perhaps a bit late as most things have been said but my Dad is an alcoholic (never admitted by him) and my mum only left him last year. I begged her to leave him when i was a child from 11ish onwards and she never did. He was rarely violent (early incidents stick in my mind) but the agression, the hold he had over my mum (and kind of still does) was debilitating for her. She blamed herself entirely and hated being so weak but always thought it was best to stick it out for the sake of money (they had none but she had so little self esteem because of him, that she didn't think she'd be able to manage!) and me, despite my begging to leave.
I resent her a bit for not leaving, although she means the world to me, and i know if she'd left, me and my life might have gone differently and i might not have my little boy (every cloud).
But i would recommend you leave him, especially if he's violent. My mother is nearly 60 and alone for the first time in her adult life, she has no confidence and can never forsee starting a new relationship, if she had left sooner she might have found someone else or had a bit of a life. His attitude towards alcohol still hasn't changed and i think he would save a can of beer over me (his only child) any day. He had a wonderful wife, nice house and could have been a perfect family man but for the booze. my mum always said he made her laugh and wen he was sober he was fine (he wasn't, he was always a bit of paranoid, self involved t**t)
My Mum's lonely, he's oblivious to anything or anyone, manipulative and a pain in the arse and my DH can't have a drink more than 2 nights a week because of my obsession and controlfreak behaviour over alcohol.
Do what's best for you. My father still won't admit he has a problem and never will. good luck