Does anyone happen to know the name of this fanfiction?

The story is about Bella and Edward who meet in a subway I believe, and the strike up a friendship. Bella talks a lot about her sister who lives with her in her apartment, and she wants Edward to meet her, but her sister always comes up with excuses. Turns out that Bella's sister is actually dead, but Bella has been taking this medication ever since she died, so she is hallucinating her sister. Edward finds out about this, and talks to Carlisle, his dad. They tell Bella that her sister is in fact dead and that the medication is making her hallucinate. Bella stays at Edwards place and goes through some sort of rehab - to get her off the medication. She has a lot of withdrawl symptoms, and yells at Edward alot.

Thats pretty much all I know. I know it may sound a little confusing but I tried to word this in the best possible way, plus it's been like 2 years since I've read this, so it's a bit hard trying to remember every single little detail.