bitchy adj.

Old English bicce "female dog," probably from Old Norse bikkjuna "female of the dog" (also of the fox, wolf, and occasionally other beasts), which is of unknown origin. Grimm derives the Old Norse word from Lapp pittja, but OED notes that "the converse is equally possible." As a term of contempt applied to women, it dates from c. 1400; of a man, c. 1500, playfully, in the sense of "dog." Used among male homosexuals from 1930s. In modern (1990s, originally African-American vernacular) slang, its use with reference to a man is sexually contemptuous, from the "woman" insult.

BITCH. A she dog, or doggess; the most offensive appellation that can be given to an English woman, even more provoking than that of whore. ["Dictionary of the Vulgar Tongue," 1811]

Bitch goddess coined 1906 by William James; the original one was success.

adjective suffix, "full of or characterized by," from Old English -ig, from Proto-Germanic *-iga- (source also of Dutch, Danish, German -ig, Gothic -egs), from PIE -(i)ko-, adjectival suffix, cognate with elements in Greek -ikos, Latin -icus (see -ic). Originally added to nouns in Old English; used from 13c. with verbs, and by 15c. even with other adjectives (for example crispy). Adjectives such as hugy, vasty are artificial words that exist for the sake of poetical metrics.

"to complain," attested from at least 1930, perhaps from the sense in bitchy, perhaps influenced by the verb meaning "to bungle, spoil," which is recorded from 1823. But bitched in this sense seems to echo Middle English bicched "cursed, bad," a general term of opprobrium (as in Chaucer's bicched bones "unlucky dice"), which despite the hesitation of OED, seems to be a derivative of bitch (n.).