By the time I get home I've got 40 minutes of brain left. Career-switchers, how do you study?

The day job flattens me. I love the idea of coding in the evenings, but most nights I open the editor, stare at it, and close it. Weekends I feel guilty resting and guilty studying, so I do neither well. For those who switched careers while working full time, what did a realistic week look like? I don't need inspiration. I need logistics.