Wrote a post and it disappeared.
Many people think like you. The whole I would never allow that to happen. Thing is you just don't know. Abuse is so stealth by the time it gets to physical violence towards the spouse and kids psychologically the person is so beat down they often think they deserve it and they are helpless to stop it.
If you look you will find a forum here for adult children of alcoholics. Check it out. I suspect you will find you relate to a lot of it.