For your Boss, replacing you will take much longer than the 6 week sabbatical she's giving you, AND it will probably cost her more than your salary in that interim. So if you're quitting today, she'd like to take the gamble that you stay. Her gamble is that you are actually happy at your gig as you say you are, and she can save herself a whole lot of hassle. Worst case scenario she loses a month of lead time on an at-least-3-months headhunt. A bit of a wincer, but you can try to make that easier by letting her know as soon as you know that you're done.

If the job market was different, then I would be much more timid about the open strategy. If you do, in fact, dislike your job and are never going to come back, then you're changing the odds on the gamble and hurting your Boss unnecessarily. This could all backfire if your Boss doesn't value you as much as you think they do, but no one is usually off-base on that.