Oh man, How frustrating and sad, but yet in a way I'm glad another Tuesday happened instead of the alternative.
And I love the way you left the ending unresolved like that. It gives the reader hope that they survive and eventually find a way to get to Wednesday.
I usually don't like endings that leave me hanging. But this one worked.
Thank you for the good story.)

that is just a cruel way to end Dean's life in the time loop...thinking that he was dead and wasn't and then all that...good job

Aw, I knew it couldn't end any other way, but still found myself hoping this might be it. That's how good this was! You really had me there, hon.

The mix of POVs was a particularly nice touch, too.
Just a truly awesome piece of work. I'm glad you put it out here for us!

Awesome job. I loved this one.

Poor Sam. Why couldn't he have stayed that Sam through season 4. The one who saved Dean, who was thrilled to have him back, who treated him as a precious blessing a second chance. WHERE WAS THIS SAM? Sigh. Cause let me tell you the lying, sneaking, full of himself, trust a demon over my own brother, seeming more bothered by Dean coming back than anything else, throw his time in hell back in his face, I know better than God Sam? They coulda kept that one on the cutting room floor. Honestly if it wasn't for the whole angel story and the incredible characters and relationship of Dean and Cass, I would've dropped this show this year. There were actually times I hoped they'd just split up so I could skip the Sam/Ruby episodes because they were just painful to watch on screen and then just watch the Dean/Cass ones. Dean and Cass were no Sam and Dean, not like you've done so well here, but the were helluva lot better than Dean/Season 4 Sam, there wasn't even really more than a one-sided relationship there. One more year, hopefully they'll make it a good one.

Dammit! You could have gone AU at the end and let them out of the loop and let Sam find a way to save Dean! I'd forgotten how much angst there was in this one. Good job!