To dream of a bare mattress represents an unsatisfying or uncomfortable situation that you are choosing to stick with. A bare mattress may be a sign that you feel some area of your life is missing something or isn't good enough. It may reflect situations where you are preferring to relax in an uncomfortable way as a means to avoid more even more uncomfortable.
Example: A woman dreamed of escaping her work colleagues on a flying mattress. In waking life she was trying hard to get away from her work colleagues fighting because they were getting on her nerves. The flying mattress have reflected to her choice to enjoy herself alone doing something she didn't really like, but preferred over being with her colleagues.
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