Detaching isn't about not having a wide range of feelings, it's about letting those feelings control you. If you find yourself losing control, remove yourself from the room, take a walk, take a shower, go to the store/library, anywhere but where you are feeling these emotions.
I too am struggling with anger towards my W. Anger is normal, and perfectly justified. I'm angry my wife is giving up, that she's willing to sacrifice our family's wellbeing for a fantasy life. When I feel this way, I carefully drive on some errand, and then park the car and just scream. It doesn't always help, but I figure it's better than letting my anger fester and grow.
I love my wife, and I wish things were different. Eventually you'll get to the point where you accept what's really happening, and the anger will get worse. Then it will mellow to something else.
The important thing is to remember that you can control your actions, but not your emotions. The best thing about my sitch is realizing this.
