Would I be out of line in confronting my stepdaughter about the way she treats my wife.
You're wife might get annoyed. What makes you want to confront your stepdaughter?
I don't know, she's a sweet girl and a wonderful kid, but a few times I've seen her be a little supercilious.
It's okay to stand up for your wife if you see her being verbally abused by your stepdaughter. Talk to her and let her know how you feel about the situation.
I think I'll try. You don't know what it's like to be in a marriage like that.
I think it's great that you're willing to talk to your stepdaughter. Your wife will probably like having help with the parenting.