I used to have this. Every year I wrote all my anger out, and burn or shred the paper. Sometimes I took it to the river and watched all the pieces float away until I couldn't see them anymore. I even brought it to therapy. I finally got tired of that jerk taking up space in my head. I went on and met my current husband about a year later.

Don't do too much physical stuff. The last thing you need is being sore *and* angry.