Who ever really believes Amy Whitehouse died from alcohol poisoning?

Winehouse?  I don't know the circumstances.  I had no trouble believing substance abuse did her in though.

Amy Winehouse was a brilliant singer who, predictably, was headed to tragedy.

As to her murder, I had not heard anything about that. Details?

Who is the Amy Whitehouse person?

If you are speaking about Amy Winehouse (not Whitehouse), no I don't believe she was murdered.  Whether it was alcohol poisoning or her body just gave out from all the drug & alcohol use/abuse, I don't think it really matters.  If you want to blame someone, do what her parents did and blame her ex-husband.  He is the one that introduced her to hard drugs.  But, IMO, her drug & alcohol use spiraled out of control and she became a victim to it as so many others have before her and, so many others will after her.