IMO the better ending is Alicia leaves voluntarily. Renoir doesn't destroy the canvas. And the whole family goes and gets some fucking therapy or some shit.
The thing about that is that as long as the painting existed in any form, Aline was almost certainly going to keep trying to get back in there to hang onto that piece of her son, and Alicia would probably be trying to jump back in to live her other life. Renoir said that staying in there warps you, and it seems like those two were definitely at that point.
The family, or at least Aline & Alicia, were totally obsessed with the painting for different reasons. While I wish that there was a "Just hide the painting and let the residents live" ending, I don't think that Renoir was ever going to let it happen because his wife and daughter probably would have kept trying to find it over and over until it was destroyed. It just wasn't worth keeping around to him.
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