How do you guys read books that you don't feel like reading?

I consider myself a decent reader. If I'm very interested in a book, I'm able to stay up all night, reading it as much as I can until I feel like if I read anymore I'll get fired for sleeping on the job. I love to read fantasy books, but usually most interesting fiction books are able to keep my attention.

The trouble I've got is with non-fiction books. Books that are talked about as "must reads". Books like Sapiens, The Selfish Gene, Pale Blue Dot, or any textbook/technical documentation. I've tried again and again to read non-fiction books. Breaking it up into smaller chunks, listening to them as audiobooks, or just slogging through it page by page. But nothing seems to stick in my head if I grind through them.

Now, before you go "Hey naznsan, just don't! Life is too short to read books you don't want to read!", the thing is, I want to read these books. Some of them explain things I'm decently interested in. Some of them I have to read for work/education. I just seem to have trouble either focusing, staying motivated, or retaining any information in such books.

So does anyone have any tips or suggestions on how I could read such non-fiction books like I read my fiction? Or am I doomed to just slog through page by page, relying on my notes to do all the remembering?