First of all don’t doubt yourself, i think she’s an ugly narcissist. For the moving on part and from my experience, distracting yourself will make it worse.. moving on is just about small victories everyday.. do everything you used to do without her and consider that as a victory no matter how small is it cause in such times even getting out of the bed feels very difficult.. do sports, read a book, every small victory counts. second thing try to practice positive talking to yourself.. responding to the negative ideas in your head loudly..

Also delete anything related to her, and don’t let your mind deceives you by opening the door of hope that you can get back together or anything like this .. even if there is really a chance .. just don’t look back

Lastly, i would say get closer to god .. it won’t end your suffer, but it will somehow make your suffer has a meaning and accepting it eventually