Breakups

Hey so my ex and I broke up about a month ago and it’s been extremely difficult to deal with. It’s gotten better but it’s still so hard not being able to talk to him. He told me when we broke up that he hopes him and I can still be good towards each other and talk yet he pretends I don’t exist. We dated for almost 3 years and I guess it was so easy for him to do so. Any advice on how I can just make the best out of the situation?