panglossian 

Blindly optimistic, naively so.

That poor sod BazzA is acting somewhat panglossian about that lovely young lass...

panglossian by BazzA May 28, 2004

Panglossian 

obnoxiously happy all the time. even worse than the most optimistic of Pollyannas

Kyle always had a very panglossian view of life, until the day he found out his middle name was Pollyanna!

Panglossian by JohnnyB.Emo September 16, 2021

pessimistic panglossian 

one who thinks that this is the best of all possible worlds, and screwed up as it may be, can't get any better.

She didn't bother to get out of bed anymore, her pessimistic panglossian perspective made life seem pointless.

pessimistic panglossian by sircasey February 15, 2009