The speaker begins by admitting they can't honestly say they're happy for someone else's good news, then spends the rest of the poem circling back to a different kind of happiness. The line "Truly, I am happy! For me" is the turning point: the joy isn't for the other person at all, but for the speaker's own escape. The person has been crossed off the list of "possible regrets," so the speaker no longer has to wonder what might have been.
What makes the poem sharp is its tone. It sounds polite and almost cheerful on the surface, but there's a cold edge underneath. The speaker takes a small, smug pleasure in having a "superior understanding" of how people behave. The final image is the strongest: the other person won't be remembered as a hero, only as a face whose mask was pulled off. The mood is guarded, sarcastic, and a little bruised, the voice of someone who is relieved but still carries some hurt.