Why is Ivan so “ashamed” when the Colonel looks at him and recognizes him?

   “After the ball,” by Leo Tolstoy, Leo has his main character, Ivan Vasilevich, tell his love story. Ivan Vasilievich claims that everything in his life depends on chances, as he recalls how the direction of his own life changed one night after a ball. He left the ball drunk with love after dancing with Varenka, the beautiful daughter of a colonel. Unable to sleep that night, Ivan wandered towards Varenka's home. 
    Near her house, he saw a military procession and heard the sounds of a drum. A runaway Tartar was being fiercely beaten under the control of Varenka's father. Filled with grief at what he had witnessed just because the Tartar ran away, Ivan questioned what the Colonel knew that he didn't.  Could the Tartar have done something more than just ran away for such a brutal consequence? But regardless, Ivan believed no one should be beaten that way. As he was watching the Colonel, the Colonel looked over and recognized Ivan. Ivan couldn’t decide what to do because he was shocked and so disappointed in the Colonel and himself for just watching.  He didn’t know if he should help the Tartar or leave. Ivan felt humiliated and betrayed at what he saw the Colonel could do under that white upswept mustache and radiant smile.  Ivan chose to leave. He felt at fault and ashamed for not helping the Tartar that night. As a result of this significant event, Ivan decided not to do any of the things that he had planned to do in the future. His love for Varenka fell apart and soon came to nothing. Ivan's love for the beautiful girl subsided away, because thoughts of her lead back to memories of the Colonel.