The TV show is really a simplified version of the books, there is a LOT more characters and plots happening in the books. Also the TV show tends to get sloppy in the writing for dramatic effect, so they will have characters do and say things that are out of character and/or don't make sense just to set-up a cool looking scene or to rush a story-line along (this happens a LOT). The books are much, much, much better written in every single way possible. They are also massive tombs. The fact that he is a slow writer only makes things worse.
It is extremely unlikely that we will see the real ending this decade. Rutgers will get it's full B1G payout share way before that happens.
Heck at this point, I just hope for the Winds of Winter to be finish this decade!
The nightmare case is that he will die before finishing the final book. Which would be tragic in so many ways.
At least with the TV show, we will get some kind of ending, even if it is just the Hollywood version. Better than nothing, right?