hi there, i'll help this out of the green room for you.
to start this review, let's talk about language. the personification of winter is really interesting paired with henry, because winter is obviously the antagonist here. i assume that the character of henry, who i assume is based off of you, is dead. it also seems that it was unexpected, or at least tragic. the dialogue at the end is from people who're mourning them, but the people who are mourning them are only missing them now that they're gone.
with what i've mentioned about language creating this atmosphere, there's also some areas that are dragging it down. most of the actual descriptions are quite medieval in how they are worded, like in "a child! hurry henry, i see no breath" because it ages the poem. i'm a big fan of using "weird" words or odd ways to describe something, especially if it benefits what i'm trying to say with theme, but sometimes it doesn't work well.
maybe say the lines aloud? i think that may help smooth out some wrinkles that i've found with lines that have been extra wordy. it's not for everyone, but usually if something doesn't sound right, you'll probably notice it if you end up saying it.
besides that, let's look at techniques and/or aspects of style here. i see a lot of unique punctuation choices, such as exclamation marks and em dashes. personally, i could go without those, but i see what they portray. the exclamation marks are there for the emotion, to showcase that it is of emphasis to henry/you. the em dashes are there because they show continuality in the lines and that everything is connected.
poetry is based on personal preference, so it doesn't really matter, but i think that ditching the em dashes would help you out big time. i won't pick on their misuse that much because poetry isn't grammar based, but i think that they are incredibly overused. end-stopping would make everything smooth, but it would also benefit the harsh tone of winter and death and possible betrayal by whoever is speaking in the poem.
that'll wrap up my review. i think this is really interesting, and i'd love to see more from you. the whole henry being personified as the author is actually really poetic, and then there's winter somewhat humanized and such. it's really nice to read.