Which of these 2 options is most likely to make a 23 year old ex want to come back?

A--sounds to me as if she is just stringing you along. You know what they say, you don't know what you got till it's gone. When you confess your love to her, she knows your still in the palm of her hand and she's in safe mode where she can still have you around. The fact that she moved on so quickly tells me she is no longer all that interested and is just dragging you around for the ride.