Again, I'm almost at a loss to find fault in this poem. My only suggestion is to change 'a participant lacking' to 'a lacking participant' because I was kind of waiting for what the participant was lacking, but then I realize that the person, itself, was just lacking. It seems to make a bit more sense to me to word it the way I suggested, however, if the way it is written now is the best according you to, then that's fine, too! It is your poem after all and not mine. 

I think it's really interesting how you wrote, "The week slips hard," because of the (contradicting?) kinds of imagery in that line and the next one, as well. The whole stanza makes me think of, "well, this week was horrible but it isn't anyone's fault - i chose not to make it better, i guess." That kind of tone sticks throughout the rest of the poem, and I really admire that! It has a lovely touch and really works with the title (it makes me think of a weekend ending on a somber note). 

The last stanza is the most interesting to me - it paints the most vivid picture and is the strongest stanza in the poem, in my opinion. I enjoy the build-up of strength in this poem because it's oddly hypnotic. What a lovely read.