I feel the same way. I started feeling a little overwhelmed by all that I had a couple of years ago. I realized my taste was changing, I was tiring of some of it and had no more space. This left me with a lot I wasn't crazy about any more, but still needed to use. So I went on a 'Only-Buy-What-I-Really-Need' spree.
I went from a large walk-in closet with 18" deep shelves floor to ceiling, to 2 rolling carts (6 drawers each from IKEA) and 2 shelves of backing/larger cuts. I like it this way. I have a great variety, still use the old and buy some new for each project, don't break the bank, and am not as cluttered. Just recently, I've bought a few new pieces just for stash. My friends were amazed that I could pass up the sales and walk away empty handed, as was the LQS owner (who said I really impressed her, and she was happy not everyone felt this way, although she admitted she did too!).
I believe, it's too much when you start feeling like this. Then it's simply time to use some up, or donate some, and once that's done - you can reward yourself :) But I have no intention of ever having that much fabric again. I simply no longer see a reason for THAT much...some yes, too much no.
Just my thoughts...