In Love with my best friend...?

I think you should tell him, and as your best friend he should understand it. All best friends love each other by nature, but I understand it must be hard for you knowing that he won't be attracted to you the same way that you are to him. If you let him, there's a good chance that he could help you, be understanding of what you're feeling. In time you'll find someone that will feel to you what you feel for him. Though, if you feel like it's just too painful you may want to stay away from him, at least until your heart can deal with that pain. my sympathies, and I hope this helps.