She needs to find a new job, because this one has crazy expectations.
If your boss insists that you log off as soon as the workday is done, you should consider yourself one of the lucky ones. Most workplaces do not operate that way, with workers working overtime for hours a day without getting paid for that time. It’s expected that if you’re working a salaried position, you’re not going to be paid for every extra hour you work. If your job is hourly, you should definitely be paid for every additional hour, but that doesn’t always happen. It’s not a fair system, but it’s the one we’re often stuck in.
You often don’t feel like you have a choice when your boss asks you to work overtime, and that’s probably because you usually do not have a choice. If your boss thinks that it’s totally acceptable to ask you to do something 20 minutes before midnight and have it ready by the next morning, you’re probably not working with a reasonable person. Unreasonable people are very difficult to persuade in the other direction.