I think you would need to give more context for us to give a good answer. 'a good look' can just mean that something seems good. It can also be something that is done just to appear positive. So - in that case, it may be referring to throwing the party, but I can't be sure. 'you're looking at the wrong girl' is similarly unclear. I would guess that she is suggesting that someone else is 'the right girl', but again, without context, it could be anything.