I am looking for a book series that upon completion will leave a feeling of emptiness, as if I'm saying goodbye to a good old friend, when you realize the good old days were left behind. It's a shitty feeling that only comes after something great, something that left a mark on you.
I've been listening to Stormlight Archive and it's almost 200 hours of audiobook.
Especially if you also read Edgedancer and Dawnshard, books 2.5 and 3.5 respectively.
Absolutely fantastic series, totally invested.
Also can recommend starting with Mistborn, including book 3.5 of that.
Oh, absolutely agree with everything you said. Tbh era 1 of mistborn also fits what op is asking for in the "saying goodbye to a dear friend" feeling.
I'm a big Cosmere nerd, so I've been through the whole thing multiple times now.
Love Secret History as well.
Also heh, Invested. Me too, I have been for years.
Can't wait to see what Apple does with it!