I really enjoyed this poem! The imagery was vivid and well-described; in only a few short lines you were able to community a really complex emotion.

The only part of the poem that didn't really work well for me was the very end where the line is "masks my cheerfulness." For me, I read the entire poem as darkness and shadow and a grey-tinged perception of the world at the periphery, but the last line seems to indicate that it fully masks cheerfulness rather than eating away at it on the margins.

Overall, I really like what you were going for in this poem and I enjoyed the read. Well done!