A friend is an anti-death-penalty activist; her guy was executed today. It's complicated.
Do not think you didn't make a difference.
In the unchanged world, he lived, and he died, that is all. Because of you, he was loved before he died. That is everything.
You cannot fight darkness with more darkness. You can only fight darkness with light. You cannot fight death with more death. You can only fight death with love.
"Perhaps he deserved to die. But there are those that die, that deserved to live. Do not be so quick to grant the one, unless you can grant the other." (my paraphrase of Gandalf the Wizard's comments in Tolkein's Lord of the Rings trilogy; and reminder of the virtue of humility; to the governor of Texas on the death penalty)