Why would a guy try to convince me that healing doesn't mean forgetting about him?

Because he’s a mind effer. I wouldn’t spend too much time dwelling on it. Or him.

share context

He wants to know he can come back for seconds later.
The healing process is helped by time, distance, and shielding.
Shielding is the thing that insists you forget about him by occupying yourself with other things.

Men are absolutes in some respects. "Forgetting" is hardly ever "healing" hence his words. Accepting someone is gone while doing other things, grieving and moving on from each bout of grief is healing.

I doubt he has accepted you being gone tho. He sounds a bit like, as OSW said, a mind effer.

Nothing I could add would carry any weight. I'm old, you see. What would I know?

im assuming you were with him and broke up?