nyc, I honestly don't think that nondy's comments were directed at you. I actually thought they were directed at me as much as anyone, as I also have not birthed any children, although I've been around for raising several and considered myself in a "parental role" for at least two of them. Others seemed to share that opinion since they were coming to my defence.
My step-daughter was 13 when I met her, so I wasn't about to come in and be all like "Hi, I'm your new mom." I tried to be more of a friend than a parent, frankly, because I figured that was the way she'd accept me most. But despite that, she's often come to me for advice about things that her own mom wouldn't talk about. She's told me that the reason she likes talking to me about stuff is that I don't tell her what to do. I tell her what I would do, and then acknowledge that the ultimate decision is hers and she's the one who will have to live with the consequences.
I am who I am. I don't need labels to define me. They're sticky, and I hate the glue they leave behind.