Say what you will about her lifestyle choices and how she handled her fame (or her fame handled her), but the following can't be denied:
1. Her voice was incredibly unique, and harkened back to 60s Motown, which is an amazing genre of music.
2. Her influence on the industry as a whole was extremely far-reaching. She almost single-handedly revived the world's love for the style (has there ever been another example of a "dead" genre being revived to such popularity? She also paved the way for other popular singers (Lily Allen and Adele off the top of my head).
R.I.P. indeed, shame her demons got her first.
Quite sad, but as everyone says, it's not surprising, and you can't really empathise with someone who just doesn't want to help themsleves.
Uh, she'd been in and out of rehab several times.
For those interested: great version of "Someone to Watch Over Me" by Amy:
https://www.youtube.com/watch?v=gLqsIIrk5wQ