I'm not that impressed.
Premising the game is "obviously an interactive art piece" is not sufficient to bypass (IMHO) its total lack of game involvement.
I think there are better and more suitable ways to express one's ideas about loss, grieving and mourning.
A game has to primarily be a game. It may tell an interesting story, but the story has develop through a convincing gameplay.
Sorry, but I didn't like it.