While mocked by some as an invention of entitled twentysomethings, the quarter-life crisis is a frustratingly real phenomenon. The promises of adulthood — security, prosperity and contentment — are often so far out of reach that they seem fully unattainable. New York City-based singer-songwriter Mitski chronicles these pains on her breakthrough 2016 album, Puberty 2. Her versatile indie-rock style incorporates elements of new wave, grunge and sparkling electronic pop. The artist’s latest single — the disco-tinged “Nobody” — heralds a new album, Be the Cowboy, due out later this year. Mitski performs on Wednesday, August 15, at the Higher Ground Showcase Lounge in South Burlington. Sidney Gish adds support.