She still uses the litterbox the rest of the time, and it is only my husband's and my bed. Happens almost daily, sometimes right in front of us! No major changes in the household, and she was the perfect cat before this started. I have washed the bedding with odor neutralizer and vinegar. Feliway Comfort Zone spray in the area hasn't affected her, either. What can cause a change like this, and is there any hope for stopping it? I am desperate!