i have seen many cases like yours, and everyone said they are the worst one in the world, it only hurts themself. if there is no hope, cut that feeling off asap; if there is still a hope around you, do your best to save it.
If you really missing him this much, why are you trying to forget it le? our future is unkown, so "you will never know what u gotta get" from this chocolate box...
If you are still loving him, go for it lor until your heart can be set free from his memory lor~