Grieving that people and pets are gonna die on me, while they are alive. Example, affection for my cat, is tainted with grief that she is old and will die soon.
Not to mention the daily sadness when I see my parents, now in their 80's.
It is insane to spoil time with them doing this, and I guess I put myself through the grief process several times instead of one big one. Sometimes I think it is a form of preparation, but then instinct tells me the heartbreak will not be lessened when it happens. Sometimes I pray I go first, before the big deaths which are drawing closer.