Why does Margaret Schlegel reduce herself to Henry Wilcox's level

Don't you just HATE, in Howard's End by E. M. Forster, that Margaret Schlegel agrees to marry Henry Wilcox? WTF!!

This just so disappoints me. Every time I re-read Howard's End, IMO maybe one of the greatest novels ever written, I feel so betrayed. (I believe that Forster means for readers to feel betrayed, because I believe Forster is great enough at writing to intend what he does, with these sorts of effects in this sort of manner. Sure, there are times to the contrary, as well, when an author's subconscious might seep through, such that the author does something they're not overtly trying to do; but this time, with Henry and Margaret, I give Forster the benefit of the doubt, I think Forster meant the disappointment, the betrayal.)

It hurts because it doesn't make real sense for the characters. I imagine that in their lives after the novel, they'll retain some tension, as Margaret may silently regret having forsaken some of her essential moral "core" while Henry parades on resolutely and obliviously to make some more and more and more money. Margaret values the intrinsically valuable, not the socially approved. Henry's attempts at wooing her come off as diffident and emotionally incompetent. Henry generally has only money to recommend him. It's great that Margaret might reconcile herself to their union; it's even greater that she might try to better him. But as her sister puts it, "Oh no no!"

But it also hurts because it's the story of what went wrong with me, for real, in my life, but in the opposite. I'm an anti-Henry, I wanted to marry a Margaret, but all the Margarets I knew married doltish Henrys. I look at my own life, as a non-business anti-Henry pro-Margaret type human, I see my own high-falutin' education and strong interest in public service, but also I see myself as, unfortunately, someone who doesn't have the monetary capacity to support an artistic woman's aesthetic pursuits. From nearly 60 years old, and still single, I can now look back at my experiences, especially the artistic and intrinsically good women I wanted to date, or the women who have broadened perspectives, or the women with some degree of moral fiber other than mere materialism, who were in my ambit when I was younger. Those women have all married boring, wealthy husbands. Mostly the men are software engineers or financial-services advisors. Me? I'm a watercolor artist and public defender. I can't afford my own house; they live in three vacation homes. Those husbands support the women's interests in moral and aesthetic success, they traipse across the globe volunteering for worthy causes while hubby blithely stays at home to beaver along, because they can afford it. Hubby satisfies himself, maybe with paid affairs on the side, maybe he's blithely ignorant that his life remains drably unfulfilling. Wife has his material wealth to fund her worthy causes, perhaps has to turn a blind eye to the husband's blithe ignorance. I don't go overseas, I value the causes but I couldn't afford it. And I'm alone. And it just eats at my heart.