Anger Issues - Need solid strategies

Hello everyone, thank you in advance for any advice you give me. I obviously have anger issues, and would like some strategies to avoid losing my temper. When I argue with my girlfriend, the arguments usually go as such: She says something that offends me (99% of the time it is unintentional), I feel wounded/offended on this inexplicable cosmic level, I try and defend myself with logic, which very quickly turns into anger if she doesn't immediately concede to me. Once I get angry, all my logic goes out the window and I resort to yelling at her.

I feel like understanding myself and why I get angry is a good first step. I get angry because I feel that any offense or transgression against me hits me right in my moral center, and I will do anything to *win*.

What strategies can I use to curb my anger? Normally in other aspects of life (work, friendships, family) I have zero history of anger problems. It's mainly with her. And I know she isn't the problem, it is me.

Thanks.