In just four lines, the speaker describes a day that feels worn down by bitterness. The title, "Routine," matters here: nothing in the poem is a sudden outburst. Anger is something the speaker puts on each morning, the way you would put on clothes. The "abominable dealings" are never explained, so we don't know whether they are personal, political, or something more general. What we do know is that they have left the speaker with a steady, simmering rage.
The second stanza turns to food and place. Eating "a bad apple a day" twists the familiar saying about an apple keeping the doctor away, suggesting a diet of spoiled things, a kind of self-poisoning or a forced swallowing of corruption. The "cold tavern" adds loneliness and discomfort, a place meant for warmth and company that offers neither. The mood is bleak, dry, and quietly sour, with a hint of dark humor in how flatly the speaker reports it.