evermore vs forever

evermore and forever both are adverbs.

Word	Noun	Adjective	Verb	Adverb
evermore	No	No	No	Yes
forever	No	No	No	Yes

As adverbs, evermore and forever are synonyms defined as:

Other synonyms of evermore include eternally, everlastingly.

evermore (adverb)	forever (adverb)
for a limitless time	for a limitless time
at any future time; in the future	for a very long or seemingly endless time
	invariably