I am also working on a quilt for a "not favorite" family member and have a week to finish the quilting and binding.
I've been praying for her and my attitude as I go and it has helped. However I still have issues witrh picking it up and finishing it...haven't touched it in nearly a week and if I don't get busy on it, it won't get done.
I'm hand quilting and lack 3 short diagonals on three corners and about 15 or so individual blocks that are echoed and X'd.
Best wishes on getting yours done. You'll feel better when it's finished! I know I will when mine's done.
And I'll be praying for you and your SIL.