Welcome to the club! :-) On the bright side, now that you have seen the error of your ways, you will maybe use it or donate it.
I was also shocked to see just how much fabric that I had stuffed into plastic totes. I emptied all of them out and stacked all of my fabric on shelfs. Just being able to see what I have available, makes it easier to use from my stash and avoid spending so much. The downside of that is that when DH seen it how much I had, he though I didn't look like enough and he encouraged me to go get some more blenders to round out my collections. ;)