Rejecting an admit to Computer Science Graduate School and re-applying
Do apply. If you don't get admitted, nothing needs to happen. If you do get accepted, accept the position if you're in a position to do so. If you can't accept the position, then talk to the graduate adviser and see if they're willing to defer you going there by a year. Most departments will be willing to do this -- they've already found you fitting for the job, so whether you come this year or next is not all that important to them. Deferrals for good reason are not uncommon.

The point is that if you don't apply, you won't get admitted this year (if circumstances would allow you to take the position), and you don't have a guarantee that you'll be admitted next year either.