Themes
there’s a bluebird in my heart that wants to get out but I’m too tough for him, I say, stay in there, I’m not going to let anybody see you.
— Charles Bukowski

Behind the line May contain spoilers.
Our reading
An editorial interpretation.
A bluebird sits inside the speaker's heart, and he keeps it locked in. Toughness is the excuse for hiding tenderness from everyone. The sadness comes from refusing to let anyone glimpse that soft, hopeful part.
Context reviewed