Dear Celia,
I like the sentiment inscribed in the haiku. I see this as 2 definite full sentences, related to each other. That is why I recommend punctuation. Also, "meeting friends" is one thing; "having fun" is a second.
So you need to use "are" as the verb. The last sentence would change to this:
Meeting friends and having fun are what keep me sane. Jill
Haiku by Celia M.
Keeping busy helps;
meeting friends and having fun
are what keep me sane.