happily vs blithely

happily and blithely both are adverbs.

Word	Noun	Adjective	Verb	Adverb
happily	No	No	No	Yes
blithely	No	No	No	Yes

As adverbs, happily and blithely are synonyms defined as:

Other synonyms of happily include gayly, jubilantly, merrily, mirthfully.

happily (adverb)	blithely (adverb)
in an unexpectedly lucky way	in a joyous manner
in a joyous manner