sympathiser vs comforter

sympathiser and comforter both are nouns.

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

As nouns, sympathiser and comforter are synonyms defined as:

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

Other synonyms of sympathiser include sympathizer.

sympathiser (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