Which sentence is better? Are my comments about "thing" correct?
I cannot watch how animals or some living things (not thing) suffer, let alone kill or hurt an animal.
I cannot watch animals or any living things (or "thing" if it's correct) suffer, let alone kill or hurt them.
I would use the second sentence. "How" is unnecessary. I think it should be "any living things" or "thing", but I am not sure.