Personification and Enjambment.
The line "and my skin has betrayed me" implies that his skin has literally committed an act of treachery against him, which is something only a human can do; a human quality.
Each of the lines are actually a continuation of a sentence, and only come to a full stop until the end, thus enjambment was used here.
Antonyms for the word melt would be: Cool, freeze, solidify, gelled, and hardened.
Those words mean the opposite of melt, which is what an antonym is.
Hope I helped!
- Amber
1st one I think sorry if I got it wrong
