Meaning : In an insane manner.
Example :
She behaved insanely.
He behaves crazily when he is off his medication.
The witch cackled madly.
Screaming dementedly.
Synonyms : crazily, dementedly, madly
In a sane or lucid manner.
She is behaving rather sanely these days even though we know she is schizophrenic.Meaning : (used as intensives) extremely.
Example :
She was madly in love.
Deadly dull.
Deadly earnest.
Deucedly clever.
Insanely jealous.
Synonyms : deadly, deucedly, devilishly, madly