How do I stay motivated when I miss my boyfriend so much?

My boyfriend has been away for a little over 2 months, and won’t be home for another 2 months. I thought being at school would help me be distracted and I’d throw myself into my studies to keep my mind off things…. what I didn’t realize was that because I miss him so much, I don’t have any will to do anything constructive. I am extremely lonely and it’s getting terribly hard. What can I do to get out of this funk?