iTunes 11.0.1. crashes periodically

Periodically, iTunes will come up with an error saying that the data file cannot be saved. At this point, if I close iTunes and then re-open it, iTunes can't find my library. If I then totally shut my Macbook Pro down, iTunes runs fine after restart.

I do have quite a large library, close to 75k songs....could this be the problem? If so, what do I do to fix it. This has been onging for the last couple months ever since I increased the size of my library from about 55k to 75k.