What should i say to a girl that likes me but already started dating another guy is she tries to talk to me?

[Edthekid..]

This girl that i had feelings for started dating another guy recently. I would of gotten so jealous if she did this some few months back when i had stronger feelings for her, but know i don't care. She could do whatever she wants. Few months back, we both had mutual fellings for eachother, but then she started to get to know that other guy and we started to talk less and less. We also stopped talking sometime and then strted talking again. On and off Converstaion between us. Now that she is in a relationship, i am not jealous, but i am upset and idk if i will ever be able to talk to her. What could i tell her if she wants to talk to me in person or on facebook? No sweet stuff. Forget her.