I just finished the game and after having played through the first game 5 times, I wasn't disappointed at all.
There are many negative reviews regarding the story, however I thoroughly enjoyed it.
SPOILERS AHEAD
I found myself feeling compassionate for both Abby and Ellie, understanding their motives and seeing things through their eyes and to end the story with both of them parting, was what I'd hoped for. I might be being naive to the deeper meanings of it all, but I couldn't fault the story one bit and felt myself walking in the shoes of the characters and understanding them both.
Overall I massively enjoyed the game and will likely play through it again at some point in the future, but I wouldn't be put off by the reviews if you've yet to play it.