well-wisher vs sympathiser

well-wisher and sympathiser both are nouns.

Word	Noun	Adjective	Verb	Adverb
well-wisher	Yes	No	No	No
sympathiser	Yes	No	No	No

As nouns, well-wisher and sympathiser are synonyms defined as:

well-wisher and sympathiser: someone who shares your feelings or opinions and hopes that you will be successful

Other synonyms of well-wisher include sympathizer.

well-wisher (noun)	sympathiser (noun)
someone who shares your feelings or opinions and hopes that you will be successful	someone who shares your feelings or opinions and hopes that you will be successful
	a person who commiserates with someone who has had misfortune