Heaven may exist or not. I am banking it is a tale to make folks feel a bit better. Notice most religions include a hell so anyone you are envious of is being more "successful" you can let that go because "they will get theirs" in the end. Genius.
I do not think that has anything to do with depression, though. Or, meaning for that matter.
If your dream is "too hard", maybe it is time to start bitching and do it/ see what you need to do or have a more realistic dream. Unless you just like being miserable.
At least the pill pushers and shrinks may get "meaning" from that.
Or... maybe I should hang MYSELF for not having 3 PhDs, a washboard tummy immune to beer, a sprawling compound, and a vault like scrooge McDuck full of Franklins to swim in....