IN GENERAL
What do you guys think about adding the friend's target on a social network to 1. widen your social network in her "territory" and 2. awaken some possible jealousy feeling in the target?

IN MY SPECIF CASE
In my specific case I've just noticed my target has actually deleted me and I don't know when it happened and why (might also be because of lack of interest, I wouldn't exclude that 100%). This Saturday I bumped into this girl's group and sat down with her friends. After a while she arrived and sat close to me, actually pressing her legs against me and talking to me.
I was playing it aloof and tried to engage her friends more than her, and one of them seemed interested (when she saw me first she walked up to me and asked "are you xxx" even though I didn't remember ever being introduced to her).
What do you think, would it seem stupid or could it work, to add her friend?