Could it be a lack of communication between you and your partner?
I've had the same thing happen with me except it was blacked out insulting texts. For me, it was about things that were on my mind that I felt wasn't worth the potential disagreement it could create so I kept things inside. So, sure enough, when I drank these issues came up and caused a huge over reaction on my part of which I felt guilty the next day.
I've lost 3 girlfriends this way and I'm hoping to change by taking alcohol out of the equation because that was the common thing with all situations.