Take a science class on the state of fluids, gasses, and solids, it will answer your questions. I'm not here to tutor.

You're being compressed right now. Atmospheric pressure applies 1 bar (~14.7 pounds per square inch - PSI) on your body externally at sea-level. That means you are currently being compressed with 41,160 pounds of force given an average of 2,800 square inches of skin surface. In a vacuum, that compression is released to nearly zero. You would be quite effectively decompressed.

I think the discussion is about decompression, not compression. In the vacuum of space, water would decompress, freeze, and eventually sublimate into vapor.