They say it takes between 12 to 18 months to get over someone, typically. U gotta go with what you DO know, and thats that he wont be coming back. so, in the meantime, while yur mind is naturally erasing him from yur life (it takes time), hang out with friends, family, visit a new place, try a new dish; become yur own BFF and keep yurself busy without relying on other ppl too much because they may be busy themselves. Who know, you just may meet someone along the way. Good luck
You can do nothing of course, obviously, he has moved on and you need to do the same.