History..and Marriage

My mother tells me that when I was a little girl, I never talked about marriage. I never talked about having a wedding, never imgined the white dress or walking down the isle. As a younger person, (before I became an SMC) I always assumed that women "got married and then had children" as if one happened then the other.
But the thing is, I never thought about what marriage meant to me by itself, seperate from being the springboard for creating children.
My mother tells me that when I was younger I said that if I was not married by the time I was 35, that I would have a child on my own. Of course, I do not remember saying this. When I broke up with my boyfriend at 33 after realizing he did not want to marry me, I never thought "okay I'll have kids alone." Instead I sought out a husband with a vengeance. Of course, we know the story, that the husband did not materialize with this kind of pressure, and that I decided 4 years later to have a child on my own. Still one of the best decisions I have ever made, despite some of the challenges.
I got my chlld, the child that I dreamed of. I got what I talked about, and what I always desired, even as a child. I was finally a mother.
What I wonder now.. what about marriage? What is marriage?
Marriage without the inevidable children? without the "get married then have children" paradigim? I have no idea what this means, because I never thought about marriage in and of itself. The concept of marriage is one thing the confuses me and makes me think at times.
My parents have been married for 53 years. I was raised a Catholic, which means that the concept of marriage as a sacrament before God was paramount. But then I think, what is marriage to the woman who considers herself Catholic, but does not agree with the negatives of the religion? the woman who spent years on birth control, who had child out of wedlock, and who now lives with her boyfriend? What is marriage to someone who did everything in a non-traditional way? What is marriage to someone like me? I am not sure.
Today I found out that a co-worker got engaged. She is 39. Instead of feeling pangs of sadness and wistfullness that it was not me, I was genuinely there in the moment, so completely happy for her. Later I questioned my lack of feeling on the matter, for me personally. How can a 44 year old, never married woman not feel some kind of sadness when it is not them getting married? What the hell is wrong with me? I discussed these thoughts with another co-worker of mine and I kidded that the thought of marriage freaks me out and makes me want to run. I told her as we waited to pay for our frozen yogurt "Age 55, that is the age will get married, 11 years from now is always what I thought." She laughed and quizically looked at me. (the way I was probably looking at myself, but I really have thought this!)
Thinking about marriage is not with the wistful, longing angst that I felt when I saw someone pregnant or with a baby before Aidan came along. Sometimes I watch a show about brides picking out wedding dresses with my mother at her house and they interview the brides about their dresses and talk about their budget. These women discuss a budget of $5 or $10k for a dress; and how they have been "dreaming about their wedding" since they were a little girl. I am just baffled by this. How could someone spend that kind of money for ONE DAY? Seems so stupid and a waste to me.
But here I live day to day, with a man I love, who is my family, a man who my child calls dad, and this man does not go running out the door. This is a man who told me so many times that he was "not going anywhere" when we were dating, and he meant it.
How would our day to day life, change or get better if we were married?
Am I missing something?