At The Blaze: "Isn’t this basically like saying you’re sad to be alive today?"
Well, no, it is not. Otherwise, I'd have to be happy about Hitler, since my parents met in the Army in World War II.
We all owe our existence to countless murders and rapes that have occurred through the ages. When we say we are happy to be alive, we are inherently accepting the nonexistence of the completely different set of persons who would be alive today if the past did not contain its many horrors. We could never express sorrow over events in the past if we had to refrain from implicitly regretting everything that happened as a consequence of those events.
Talking about the past isn't like time travel fiction. Chelsea wasn't like Marty in "Back to the Future" (who needs to make sure that his parents, who aren't a loving couple in the present, really do get married, or he will never be born).