i cut my own slack - A cocky way of saying you're the only one who can help you,

A cocky way of saying you're the only one who can help you, and you're too proud to ask anyone else, even if they're right there.

I cut my own slack. You're still fighting with your brother, and I already got my homework done and ate my chips.

I cut my own slack. You're still waiting for the bus, and I already got my food and finished my math.

I cut my own slack. You're still arguing with your teacher, and I already got my assignment done and had a snack.