I used to date a girl with a similar problem. Sweetest person when sober but an absolute nightmare when drunk.

Initially I didn't realise how big her problem was. After a few dates, she invited me to her company function as a +1 (she had a well paid job in middle management). After a few drinks she started dishing it out to her bosses. I should have left at that point. Next thing, she lost balance and bumped into a table which resulted in pushing lots of other people's drinks on the floor. We were politely asked to leave.

I made sure she got home safe that evening and met up with her a few days later. I wanted to talk about what happened with the intention of politely finishing it all, but she was in denial and instead walked out on me, somehow making it 'all my fault'.

I actually liked her and felt bad it ended up like this, but I knew I dodged a high caliber bullet right there.