It is normal, and yes, it goes away. In the beginning, there is anger, confusion, pain, everything. When that calms we think the anger is gone, but it's just waiting. It comes back, as strong as it's ever been, and it's almost scary the rage that boils inside of us. It's for everything - the lies, the betrayal, what was taken from you, what was given to you, who you thought your spouse was, who they were during the A, who they are now. It's part of the rollercoaster.
I thought I had forgiven at about 6 months too. By 9 months, I was really wishing I had taken some form of brazilian marshall arts, or done some target practice, or paid more attention during CSI I was pissed, and it seemed never ending.
You'll get through it, but not overnight. Each stage takes time. Just vent here, or to your IC, or a friend, or whomever you can grab.