I do not have a huge stash but what I do have calls me often. I usually buy for a certain pattern but not all at once. Some fabrics are bought over time and at different places. I have given up on some and used it for other newer projects. After a while I am over whelmed like you. At this point I have to make myself a list of what I have started and another of what I want to start. I force myself to finish one or two of those WIP before I start something new. This list helps to remind me of what I have in progress. Sometimes the call is too strong to resist and I end up starting something completely off the lists. The complicated life of a quilter.