Stop talking to my ex?

ex girlfriend broke up with me 3 months ago. shes been dating someone else for 2 months but said she doesnt want to lose me from her life altogether, meaning, be friends. well i still have pretty strong feelings for her. we have been in consistent contact through this time but lately she has been ignoring me somewhat. like taking hours and hours to get back to me even when i know she could. i know she knows that i still want us to be together someday and she said it wont happen, so should i just stop talking to her to help myself heal? and if i do, will she begin to miss the communication and regret treating me badly right now? we had a very special bond in our relationship so it wasnt just some crap of one. lost our virginities to each other and such so. im a real good person, dont get mad easily at all, but ignoring me is just immature i think, at least say you have to go or something. so what do you think i should do?