sympathizer vs comforter

sympathizer and comforter both are nouns.

Word	Noun	Adjective	Verb	Adverb
sympathizer	Yes	No	No	No
comforter	Yes	No	No	No

As nouns, sympathizer and comforter are synonyms defined as:

sympathizer and comforter: a person who commiserates with someone who has had misfortune

Other synonyms of sympathizer include sympathiser.

sympathizer (noun)	comforter (noun)
someone who shares your feelings or opinions and hopes that you will be successful	bedding made of two layers of cloth filled with stuffing and stitched together
a person who commiserates with someone who has had misfortune	device used for an infant to suck or bite on
	a person who commiserates with someone who has had misfortune
	a person who reduces the intensity (e.g., of fears) and calms and pacifies