http://www.youtube.com/watch?v=qIt6KCwlFPw
(This is based on the Korean version translated into English, not the English version itself because, honestly, they're quite different.)

Leeteuk listened sadly as you exchanged vows with Siwon. The tears threatened to spill from his eyes, but he held them back.

After all, you were his two best friends, and he was supposed to be happy for you for finding love in such a cruel world.

He could remember the nights that you would come running to him after a fight with Siwon, crying on his shoulder and praying that he would be able to console you. Those nights he wished that you would stay in his arms forever. He wished that you would realize that he loved you... so much more than Siwon ever could.
But he always found himself playing the role of the best friend. Now the best man. Forever being forced to watch, stand idly by, and smile. If he couldn't make you love him, then he could at least keep you by his side in /some/ way, never revealing his heart in fear that you would reject and possibly hate him.

Please don't take his hand.
Rings slipped on fingers, and for a moment, he hated you. He wanted you to be unhappy. Honestly, this feeling found him often, in fits of jealousy. He simply wished that Siwon would upset