The policy isn't there just to be extra nice, it's because otherwise the patient dies without a liver.

Since she was too sick for a partial liver transplant, and not eligible for a dead donor full liver transplant, she would have just died.

It might seem cruel but the same is done for a lot of other procedures; if the chance of you dying in surgery is way too high, doctors won't take the risk, they're not executioners.

It's not a moral judgement about her alcoholism, the same would have been true if she had a cancer no surgeon would take on.