Hey, Dimitri. I'm Faith. Nice to meet you when I'm my trying to kick your ass.
I'm not gonna sugarcoat it and say it's all fine, but I've got some experience in being evil. What happened wasn't your fault. That was a monster in control of your body. I know you'll still feel guilty and maybe you should, because it'd be pretty fucked up to remember doing that stuff and not feel sorry. Point is, I'm not gonna hold it against you. Most won't.
As for Rose, you're nuts if you think we're letting you do it alone. This is our city, too. And no one should have to take out someone they love. Me and B, Sam and Dean, the rest of us - we're all gonna help you. One way or another, we won't let her stay like this.