The speaker is pleading with someone they love who self-harms and feels like a failure. Speaking directly to this person, they ask for a promise: that when the urge to cut returns, the speaker will not become one more regret, one more "if only" lost beneath the scars. The speaker insists the person was always good enough, strong enough and fast enough, and backs this up with memories of being held, scolded, listened to and even thrown back into the sky when they fell. Those images suggest the loved one has been a source of rescue and support.
The mood is raw, urgent and tender. The speaker's voice moves between desperate and fiercely loving, with repeated "I promise" lines that sound like a vow. The poem ends on a quiet, uncertain question, "Aren't we?", which shows how much the speaker fears the answer and how badly they want to be believed.