Your W has given you a valuable gift of input to how she perceived your marriage, and what got her to this point.
Some of it may be coming from self-convincing, or rewriting history, but look for yourself and with your IC to find where the truth is. (I say it's a gift because my H wouldn't tell me why he wanted to leave me, he said it was just too much to list. I'm getting a little feedback now, finally.)
Yes yes seek anger management because she thinks you need it. It shows you're trying in good faith, and it will likely help you no matter where you fall on the spectrum.
And to answer your question, you don't sound like a monster to me and yes, I would be afraid of you when you're slamming doors. I'm sensitive to my perception of violent anger. My parents argued when I was little and slammed things and broke dishes, and I hid in a closet. And they were great parents, not perfect but not abusive at all by the standards of the day (meaning there were definitely spankings). But to this day I can't bear slamming doors. Once my H threw a carseat in the garage because he was mad and I felt (irrationally) terrified.
I'm not saying I was correct to be afraid. But you see a lot of people here who feel upset when their spouse is upset - their emotions are sort of entwined and they have lost control of theirs. If your W felt afraid simply because you were showing anger, she may be in that boat too and could learn more about boundaries and that "you are responsible for your own emotions" and such.
But it would be helpful for you to understand if she has a very low tolerance for physical expressions of anger, why that is, and how you can productively express and/or feel your own emotions without frightening her.
I think there's hope.
Adinva 51, S20, S18 M24 total 6/15/11-12/1/12 From IDLY to H moving out 9/15/15-3/7/17 From negotiating SA to final D at age 50 5/8/17-now: New relationship with an old friend __ Happiness is a warm puppy.