Othello Post 2

Why does Othello tell Desdemona this origin story about the handkerchief?I think that Othello tells Desdemona this story to make her feel guilty. I think that because he has suspicions about her cheating and now that she has lost the handkerchief, he is using her loss of it as a way to make her feel guilty for what he thinks she has done. I think that he even describes the meaning that it has to his family to make her feel even more guilt because I feel like when you lose something that might have significance to someone it makes you feel worse about losing the item. I feel like Othello thinks that if he mentions his family she will feel even more guilty about losing the handkerchief. Also, because Desdemona is so consumed and in love with him for his storytelling, she will believe this story that Othello is telling her even if it is not true because she has believed all of his stories so far. Overall, I feel like Othello is using the handkerchief loss as an opportunity to get back at her for his thought that she is cheating on him. 
It feels like Iago has deeper motives to destroy Othello’s life than just because he did not give him the position and because he suspects him of sleeping with his wife. What could those other movies be? Is it because Iago is jealous of Othello’s life and wishes that for himself? Also, is Iago just a pure evil person or is there a reason and motive for his evil actions?