loyal
loy-al
adjective
Remaining faithful and committed to a person, organisation, or idea.
"She is a loyal friend who always supports me."
Thesaurus
Synonyms: nationalistic, ultranationalistic, flag-waving, chauvinistic, jingoistic, superpatriotic, patriotic, true-blue, allegiant, liege, hardcore, doglike
Antonyms: disloyal, unpatriotic