I lost my sewing room when my son came along. I feel your pain, but I got a whole basement (yeah, whoopie, in the dungeon) for my sewing. Oh and the treadmill, my husband weights, freezer, panty cupboard, the washer and dryer, furnace....
But I have heard a good way to store fabric out of site is between the mattress and box springs, or maybe the crib mattress and springs.