Oh Lisa. I feel ya girl! When STBXAH was still living here, there were times when I literally thought the top of my head was going to pop off or worse yet that I would start beating the cr#p out of him. You are not alone. Those ladies at Alanon have probably learned how to detach from their situation or left their AH's and that's why they are serene right now. I bet if you asked them how they were doing in the beginning they would tell you that they felt the same as you do right now.
Get in your car, close the doors, turn up the music really loud, and SCREAM. I have done that on countless occassions. I slap my steering wheel too. Just something to get that energy out. Now that STBXAH is no longer here, I rarely have these "fits". I do still get mad as hell at him initially but 5 seconds (or less) after the initial spurt, and I'm done. I just don't care about his cr#p like I used to. I'm "over it".
If you want a more healthy release, go for a run or go hit the gym. It's just the energy in you that needs to come out. I wish you peace and serenity. It's there for the taking. It will get better if you start focusing on you. I know you think this mumbo-jumbo sounds like BS right now, but I swear it works. You really can move past the anger once you decide that your AH is not worth it and YOU are.