When your stash takes over the house or you need storage lockers or trailers to hold it, it's not a hobby anymore ... it's OCD - compulsive hoarding, just like those who hoard pets or food, junk, papers etc ...
We had a dear lady in our guild who never let anyone into her house, it was stacked floor to ceiling with fabrics, books, patterns and junk. Even the kitchen & bathrooms. Her house was unlivable and she really suffered for it. She couldn't find things and she had NO place to even sew and quilt - unless she went somewhere ELSE to do it !!
Friends offered to help her sort it all out but she never agreed to the help. Her sons finally gave most of it to the guild & bees (per her wishes) and the rest to goodwill, when she had to go into assisted living. She never even used or enjoyed what she'd bought. Very sad :(