No your not doomed forever. Just spray the soft furnishings eg mattress, carpets, sofas. Wash any cat beds or soft blankets they've slept on. You shouldn't need to wash all your clothes. Once both cat's have been done you'll have 2 little flea bombs walking around your house. vacuuming will take care of the rest. A good enzyme cleaner will help to stop the cat that has been spraying not go back again.