Oh I've definitely been there. I'm a university student, and breaks between semesters are the worst. What I do to help was working on something I liked. The last few breaks I would take an online course to keep me busy (unfortunately that is a pricey option). Since this break I don't have the funds for a winter course, I've been committing myself to practicing guitar, and forcing myself to do so by recording how long I practice and trying to meet a weekly quota. Those are things that have helped me, hopefully you can find something to occupy your mind as well.