I often feel that way - but - I think a lot of times people say things (like getting hit by a bus, etc) simply because:

they are trying to remind us to live each day for all it's worth and/or
because they don't know what to say, but feel they must respond.

Somedays I wish we had a pause button like on old tv shows, where the world would temporarily freeze and we could blurt out anything to blow off steam, then hit play after we got it out of our system.