I think every young person, including myself, tries to have it all and we don't realize that something has to be sacrificed. For awhile I wasn't willing to fully dedicate myself to my startup because I knew that to do the best I could it would have to become my life. What killed me was that I had just graduated and felt that I would lose all my great new friends and lose my weekend social life. It took me a couple months to realize -- So what?
Unless it's your health or spouse/kids, pretty much anything is worth the perceived "sacrifice" when you're pursuing your own calling. Waking up each day with that enveloping purpose and drive is such an awesome feeling.