Suffice it to say, I found these questions to be good ones, ones that Trek doesn't tackle enough. The ending is probably most controversial for many people. You may have found it manipulative, without realizing how true it is. Every day people die. You don't know them, I don't know them.
Life is inherently ephemeral.
The fact that even their accomplishments became nothing says a lot. I think Voyager never knowing about its double, passing it like two ships in the night, says much more. That and focusing it on the perspective of the doubles are the two primary reasons it worked so well in the first place. Thus, saying the episode was bad because it never happened is hardly the point. It did happen.