ABSTAINER, n. A weak person who yields to the temptation of denying himself a pleasure. A Total Abstainer is one who abstains from everything, but abstention, and especially from inactivity in the affairs of others.

Ambrose Bierce (1842–1914?) American writer and journalist

“Abstainer,” The Cynic’s Word Book (1906)
    (Source)

Included in The Devil's Dictionary (1911).