Why not hire her as a backup singer, tambourine player, or teach her guitar riffs???
.
.
On the laptop I had the soundcard going out the phones jack into the mixer into the interface which goes back to the laptop via USB. I haven't looked into this yet so who knows.
I don't fully inderstand the USB connectivity thing as there's no real control for it.
I monitor thru the interface headphones or speakers connected to the interface main outs.
Another issue is the interface volume control is supposed to affect the speaker outs but it doesn't.