it's almost like this is the first time Emma can truly exercise her powers independently, now that Miss Taylor has become Mrs Weston, and her tuition is done. She thinks she is responsible for this match, so might as well make another. Probably like playing a game, or her fondness for riddles and things. Elbe's reference to dolls is probably quite interesting. And Emma does not see it, she thinks because her intentions are good, all will work out like in the Weston case. We shall see what happens.