You can't include tuition paid by anyone else as you providing your own support anyway. So that doesn't figure in. However, support is not defined in monetary terms only. If you used any schoarships, grants, 1099-Q funds or anything else that is not "your" taxable money, then you did not provide the support. For example, if you lived at home or with your grandparents, or a friend's house, and you don't pay rent and/or don't have a legally recognized rental contract to prove you did, then whoever housed you provided you housing. You didn't provide and pay for your own housing. That counts as support provided to you by a third party. Macuser's reference will work you through this.
