I Keep My Emotions Bottled Up

Honestly, I don't know why I'm here, other than because I have a lot of bottled up emotions. I let some out occasionally but the other day I drew it close. Everything was getting to me, and the 'bottle' was about to explode. The trigger: my girlfriend had a bad day and was snapping at me. She kept saying I'm sorry, and I had to leave, I had to walk away before I snapped. I did snap, just not at her, let everything out in the shower. I don't care what anyone comments, but if you have advice I would gladly take some.