How can i tell my ex girlfriend to STOP?

Me and my ex are 14 and went out for a year but we argued a lot and i just couldn't take it anymore so I broke up with her. And its been like 3 weeks since we broke up and it seems like she always has something to say to try to start a conversation( communication is through text). And yesterday she even sent me a song through a voice mail on my phone about how she loves me and i love her and how were meant to be and stuff. Shes also making a video for me she said and she's gonna finish it tonight and text me how i can see it. And she still always say she loves me and everything. and today is (if we were still going out) our 13 month anniversary and she texted me in the morning and said "happy 13 months of loving each other<3". and its not like i don't appreciate it, i think its nice but she was never this nice while we were dating and i hate talking to her cuz of some stuff she said\did to me(one of the stuff she said to me was **** you because she thought i was lying about something when i really wasn't). And i don't want the video shes making and i don't want to talk to her anymore. How can i tell her to stop?