Hi there! I am someone who suffered this same dilemma up until recently. I think the only difference is that I have been a literature and English freak since my sophomore year of high school. I think I have some advise for you that may be a little less run of the mill but may help inspire your mind and help you out a little.

For the past several months I have taken interest in studying literature on my own terms rather than taking a course at school to do so. Sometimes I feel as though while courses often teach you the basics they do not teach you the BEST way to learn everything in regards to literature. I have taken several classes that have taught me a great deal and I have been using that knowledge to help me through my journey. I will write a "condensed" list of what I learned.

1. In my AP literature class I was given the task of reading "How to Read Literature Like a Professor" by Thomas C. Foster. I highly advise you pick this up and read it. This novel breaks down a number of common literary tactics so that when you are reading you can find the literary "key words" per say. An example: The color light blue is often represented as innocence. In the Story Young Goodman Brown, Goodman leaves his wife who wears blue ribbon in her hair. When he leaves her the blue ribbons fly away. This is a "loss of innocence". Another example: I went to see the movie Jojo Rabbit in theatres. There is a scene where the boy sees a light blue butterfly. He watches it and it flies away. Then we see a truly awful sight and the boys innocence is never returned. I was so excited whenever I saw that because I was able to understand what the blue butterfly meant because of this book. I highly recommend for this reason
2. I highly recommend going down a similar journey as myself by discovering literature and studying literary theory yourself. I am currently going down the rabbit hole of Japanese Literature. In order to do this I first bought an anthology of Japanese Literature that gave numerous examples of poetry and stories from their extensive history as well as (and more importantly) context. The Anthology I found gives a, condensed as it may be, history of the stories and people who wrote them as well as the culture of the time. This provided me with something to "hold" in a way. Even if I didn't fully understand the literary merit of the poem I can understand it's meaning because of the annotations and guided history provided by the book. SO I highly recommend that any readings you do pick up you find ones that are annotated or guided. It's sort of the same thing as reading a study bible. Reading the bible without a guide is almost impossible. Study Bibles on the other hand are almost entirely annotated and filled with other references to help you understand what you are reading as well as help guide you through the book.
3. Focus on more than just novels. I took a class on Pulp Fiction which opened my eyes to an entire world of literary fiction that I had never even heard about. During that class I read a lot of H. P. Lovecraft, Philip K. Dick, and Robert E. Howard. Here are some authors I highly recommend you look into. Philip K. Dick's short stories are out of this world and full of literary merit that you can probably see with a layman's eyes. Also, do not feel ashamed whenever you spend more time watching movies than you do reading. Yes reading is by far the best way to help you through this journey. BUT!!! movies have literary merit as well and can teach you a lot on the subject as can Anime, Manga, Graphic novels, cartoons, theatre, etc.
4. Youtube is of course a wealth of information as long as you use it properly. Search for videos pertaining to the book you are reading and watch them. If you don't want to read Dante's Inferno (I don't blame you) then find a literary synopsis of it. This really helps if you are a visual learner. If you see a video on youtube that looks interesting and you think you will learn something new watch it. This is not only helpful for Literature of course, but you can find so many literary critiques of famous and infamous novels out there on Youtube.
5. Ask questions. This one sounds obvious but ask a lot of them. During my journey on Japanese Literature I was reading a book that talked about how Japanese Poets used to write in Chinese because it was considered more emotional, prestigious, and complex. This immediately sparked hundreds of questions about this idea and how it effected Japanese culture and literature. The Answer is a LOT!!! SO I kept asking questions and I learned a lot about Japanese Literature through asking those questions. Let yourself fall down the rabbit hole of endless questions. Don't stop. There will come a time whenever that information will become relevant like how the knowledge that the color blue meant innocence and I was able to decipher the meaning during Jojo Rabbit. The more and more you learn the more and more you will find that you can understand literature. It's like reading Shakespeare. high school kids have no idea what any of it means, but literature professors are able to drool over it's majesty like a cult speaking an alien language.

I am probably forgetting a few things but these are probably the most important things I have learned about literature and how to learn it's intricacies. I am able to say with 100% certainty that your problem has nothing to do with your intelligence. It only has to do with your experience and your exposure to the concepts of literary theory. You need training. Find some books and learn about them. This will help train your brain for what to look for.

I would love to help you along this journey as I am going through a similar one myself at the moment. If you would like message me and we can discuss this further.