I'm tricking my best guy friend and I feel guilty! How do I end this the right way?

[Sarah]

So I've known my best guy friend since sixth grade. We've always enjoyed each other's company. However, I realized that I had feelings for him about five months ago. However, he sees me as one of the "bros" and just doesn't see me as anything more as a friend. I tried to forget about him and went on to date someone.

About a month ago I found out my boyfriend was cheating on me when me and a friend used a fake email and stuff to see if he was seeing someone else. I was depressed, and while my best friend comforted me, I began to develop those feelings again.

Right before Thanksgiving, I made a fake Facebook using the fake email and stuff and friended him, acting like some girl he saw at a party. We began chatting and I began talking dirty to him. He seemed to return the gesture and we really began connecting. As a tease, I sent him a picture of my cleavage (without my head or any recognizable jewelery) and he admitted that it was hot!

However, now I'm worried that this has gone too far. He hasn't figured out who he's really chatting to, but he's now talking about meeting me and stuff! And after our raunchy chats it's now so awkward to see him in my classes! If I come clean, I don't know how he'll react. Even if he thinks his feelings are true, they were all based on my lies! Heck he'll probably be embarrassed that he was masturbating to pictures of someone he sees as a sibling!

I feel really bad for using my guy friend as some cyber-sex outlet and I need to make things right...
But like that's the thing! I've tried the serious talk with him and he just said that he only sees me as a friend/bro!