Read "B4 U Text Her." That's really one of the best text game books out there and it's a short read.
Anyway about the "Who is taken?" Restate who (your future wife) then add some kind of neg and try to steer the conversation to her asking you about your "ideal wife." If you get to this point, you tell her that the qualities your "wife" should have is her qualities, but amplified. Try making her qualify herself to you.
Example:
Her: "Who is taken?"
You: "My future wife. Find me one jerkface

"
Her: "Tell me what kinda girls you're into?"
You: (amplify her qualities) and say "Basically the complete opposite of you."
Her: "Eh? I don't understand? Blah blah blah"
You: "You and I are too similar. We'd fight and argue, I'd win, and you'll make me sleep on the couch"
Her: "Pshh yeah right... you? win?"
You: "What makes you think you can beat me?"
Something like that...