oblivion vs forgetfulness

oblivion and forgetfulness both are nouns.

Word	Noun	Adjective	Verb	Adverb
oblivion	Yes	No	No	No
forgetfulness	Yes	No	No	No

As nouns, forgetfulness is a hypernym of oblivion; that is, forgetfulness is a word with a broader meaning than oblivion:

oblivion: total forgetfulness
forgetfulness: unawareness caused by neglectful or heedless failure to remember

oblivion (noun)	forgetfulness (noun)
total forgetfulness	tendency to forget
the state of being disregarded or forgotten	unawareness caused by neglectful or heedless failure to remember