I got depressed around my 2nd year of school. I thought it was me, but it turned out that I had one absolute turd of a professor who managed to rip from me every ounce of passion I once had for my avocation.
I dragged myself through the rest of my program, frustrated at a tenure system that encourages and rewards laziness, and a system of "academia" that sees students as a necessary evil--a burden that stands in the way of doing research, yet at the same time is necessary to pay for doing that research.
I had to stoop so low as to having MY MOTHER call the department chair, something that I had never had to do in my life, but it was the only way to get her off of her ass and deal with the problem at hand.
In short, I love my 9-to-5 "grind." I love my cushy job playing 21st century sherlock holmes, trying to create a secure network, trying to create a bulletproof disaster recovery plan. That's the whole reason I suffered through school--that piece of paper was the ticket I needed to be able to do a job that I love and get paid good money to do it.
I don't miss homework and stupid pointless projects.
I enjoy the fact that when I leave the office in the evening I leave, and I don't have to sit and think about what paper is due tomorrow or what exam I have to study for next week.
Keep focused on your goal. I have a friend who wanted nothing in the world other than becoming a teacher and he has allowed that simple dream to slip from his grasp because he just can't find the confidence and spunk to drag himself through school. He just had to suffer through a couple more years and then he could be doing what he loved. Now the poor guy drifts from tech job to tech job, eventually getting fired because he's not really happy and has no reason to really make it count.
Don't let this happen to you.