Not every book will be enjoyed by every reader. I DNF once I realize the book is just not my cup of tea. I just checked and of the 15 books I started this year, I dropped 4 at some point. Sometimes I hate-read a book. That happens when I find the book annoying, but it still has something to keep me going on. I am enjoying it to some degree, while also being angry at it.
In any case, if reading the book feels like a drag, close it and open another book. Maybe you abandon the book forever, maybe you pick it up a year from now and plow through it. Both are fine.