No one decides to leave it. It happens slower than that. You handle what is in front of you. You answer what is asked. You become the man people count on, and somewhere in all that reliability, you lose track of the man doing it.
Nothing is wrong, exactly. That is what makes it hard. From the outside, things work. From the inside, there is a flatness you cannot explain, so you stop trying. You tell yourself this is what adulthood is. You tell yourself everyone feels this way.
A man rarely collapses. He drifts. The distance grows by inches – a feeling swallowed here, a conversation avoided there, a year that looks exactly like the one before it. Drift does not announce itself. That is its whole strategy.