Why Most Men Don’t Want To Get Married?

Hello everybody,
My name is Sandra and I have been going out with Michel for 9 years.
Michel and I have been dating for 9 years. We have two children together. But, my boyfriend does not want to marry me. At the birth of my first child, I thought he was going to marry me, but he still does not want to take the plunge. I talked to my mother and my girlfriends, but they ask me to wait. I’ve been waiting 9 years and nothing happens. I’m sorry. This marriage story eats my life and destroys my couple on a daily basis. My boyfriend has the impression that I force his hand, but that is not my intention. I just want us to realize our love in a solemn union. Many of my girlfriends are in the same situation. One wonders each time: “Why are men so afraid of marriage? “
I am a patient woman. I take good care of my man and our children, for he does not complain. We are, I think, a happy couple. But, this marriage story makes me feel very bad. When I see married couples, I tell myself, they are lucky to be together.
It is said, that when one is with the right person. We know it ! I know, Michel is the man of my life and I do not want to live without him. And, I have proved it daily.
Tell me, Why are men so afraid of marriage? I have to wait another 15 years, 20 years, for him to ask me. If he was not happy with me, then why, he stays with me. Why, he says sweet words to me and repeats unceasingly: “I love you. “
Love is not just words. It is also very concrete gestures. I cook for him. I take care of our home. I listen to him even if I feel he is not listening enough. I wear sexy lingerie. I leave him free to go out with his friends, when he needs it. Is it because I am too kind, that he walks on me and does not want to marry me.
I am anxious every time I think of marriage. And, it becomes an obsession. Forgive me, if I put myself so naked. But I need it. Do you think he sees another woman, that’s why he does not want to marry me. I don’t  know ! 

Tell me, what must I do to make him marry me? Why does he not want to marry me? Have women experienced the same thing as me and how have they addressed this problem? And you men, why are you so afraid to take the plunge?
Be indulgent to me, thank you, thank you for your answers.