If one thing stays with you

Let it be this.

Ya'qub grieved for years and the Qur'an does not call it a failure. The Prophet, peace be upon him, wept and said so out loud. Sorrow sits in a list with fever and injury, not in a list of sins.

And the one practical thing. The feeling comes after the action, not before it. You do not have to want to. You only have to do the small thing anyway.