。
She lives a hand-to-mouth life.
Literal
She [topic-は] that-day-living [genitive-の] life [object-を] is-doing.
その日暮らし is a fixed expression — literally 'living for that day,' the Japanese equivalent of 'hand-to-mouth' or 'living from day to day.' 暮らし is the noun form of 暮らす ('to live, get by'). Pairing the phrase with 生活 ('life, livelihood') and ~をしている creates the noun-of-doing structure: 'is leading a hand-to-mouth lifestyle.' The phrase has an undertone of precarity — it implies barely covering today's needs without being able to plan for tomorrow.