Why is my ex doing this.?

so i broke up with my ex not too long ago. And I want to get back together with her. But she decided against it and is now in a long distance relationship. She is projecting this image of obnoxious happiness to everyone. she is blowing the new relationship wayyyy out of proportion, pretty much doing all the things a rebound does. At the same time she still does things like keeping the bear i got her in her backseat, plays our anniversary for the lotto and then called me on the 20th out of the blue because the 20th used to be our day to do stuff because it was like our monthly anniversary. what and why the hell is she doing this??? I really want her back but it seems like i'm not getting anywhere.