At this point, I think that applies to pretty much everything else.
Work, relationships, life. If its not fun and worth a laugh, then just gtfo.
I think that there is certainly a time and place for, you know, being super cereal.* Ahem.
But having a sense of humor isn't just about the good times. It is the best salve for the bad times as well.
On a related note, there is nothing more difficult than trying to have a conversation with a humorless person.
*I love the phrase, but that plot did NOT age well.