When Is It Okay to Throw in the Towel?

I have a friend who gives every book 50 pages. If she's not hooked within 50 pages, the book goes back to the library, or is left on the airplane seat for the next potential reader, or into the trash. "Life's too short," she says.

I'm trying like Hell to read Pychon's Against the Day. But every page makes me more confused. I think there's a story underneath the verbiage, but I'm not sure. Whole fat paragraphs float past my eyes. I catch a word here or there, grasp at a setting, think I can discern characters, but for the most part I find myself confused, frustrated, clueless.

I felt the same way when we first moved to Mexico and I knew enough Spanish to flesh out a dialogue: Esta Susana en casa? Si. Esta en la sala? No, esta en la cocina. Trying to understand the world around me, a world that rarely contained Susana, her house, the living room or the kitchen, was like trying to read Pynchon's frustrating novel. I knew there was some important shit going down, but I wasn't part of it. I was standing on the outside of it, panicked, frantic to get in, while men and women and children danced (at least that's how it seemed) around me, pointing and laughing. For all I knew, a bus was aimed right at me.

According to my friend's apt formula, I should bail on the book. I'm around page 180, 10 or so characters and ... 7? 56? ... settings and at least 30 subplots (some of them dead ends, as far as I can tell) in. I've given P's nightmare world 3x the amount of attention my short life can afford.

And it's making me feel stupid, as well. I should just jettison it, right?

But here's the deal. I've spent 26.00 on the book. I did NOT check it out of the library.
It's fat -- heavier than a bread basket filled with pumpernickel.

I'm an English professor. Can English professors admit defeat? Or, if they can, when is appropriate? And should they just keep that information to themselves, so as not to dispel the illusion of literary mastery?

Further, the New York Times gave the novel a great review. (Well, a mostly great review.) This adds to my feeling of failure. What's wrong with me? Have I been spoiled by Chick Lit, mysteries, thrillers, and other tawdry pleasures?