A buddy of mine had the same thing happen with a 700 pager and his group split it into chunks with a check in halfway through. Turns out people just needed a deadline that was not the whole book.

Man I feel this in my soul. What worked for me was switching genres completely, went from a heavy drama binge straight into dumb comedies and cooking shows for like a week. Your brain needs a reset from that slow burn stuff, so give it something with zero commitment where you don't care about the characters at all. Took me about 10 days before a normal show could hold my attention again.

Totally guilty of that, I just let the episode count drift and hope for the best.