What should I do, I'm so confused?!?

This is normal. Sometimes people think they "like" a certain someone soo much and want to be in a relationship with them. But then when u r in the relationship, all tht feeling tht u had for them, just starts to fade little by little. Now, you're saying he is a great guy, so dont let him fall in love with you. I think you should tell him as soon as possible before his feelings for you get stronger. Just be truthful, sit and have a long talk with him. Tell him excatly what is in your heart. You probably will hurt him at first, but it's better to tell him sooner than later.