Suggestions, my dahling...

"How bittersweet of a feeling fills me"
-This line is worded a bit awkwardly, I think it's the use of the word "how". Maybe "such a bittersweet feeling fills me"?

"Spreads herself over you like butter"
-This simile sounds a little cliched and shallow to me. Something I came up with: "She holds on to your words like she's falling"... Maybe just something less literal.

"Just imagining"
-This line could be omitted. I feel like it doesn't add much.

You already know how I feel about punctuation, lol!

I do love the concept behind this poem, I feel like if you just fixed a couple of things it would be pretty amazing. Best of luck with your favorite football player!