It's a cliche that we're all used to by now, the main guy and the main girl in a story kiss, get together and live happily ever after. Well, that narrative is getting old.
Growing up I was only ever exposed to straight couple romances. I had no idea that two guys could be a couple, never occurred to me that two women might want to kiss each other. It wasn't until I read "City of Bones" by Cassandra Clare that I was introduced to my first gay character, Alec Lightwood. When we meet Alec, he doesn't seem to like the protagonist, Clary, at all. At first, I just assumed it was because he saw Clary as the threat that could expose their world (oh yeah, the kids are shadow-hunters descended from angels and they hunt demons, and Clary is one too of course).
Then later I learned he hated her because he was in love with his best friend Jace, whom Clary was getting close to, and Alec was jealous.
Reading that scene was mind-blowing for me. After doing more research I learned about the LGBT community and that romantic love wasn't just between men and women, that sexuality was much more complicated than that. But I was still reading the same heterosexual romances. I knew that the LGBT community existed but I didn't have their stories. It wasn't until I read "Ask the Passengers" by A.S. King that I read a book with a lesbian main character, and that wasn't until my junior year of high school.
Then a few years ago I read "Simon vs the Homo Sapiens Agenda" by Becky Albertalli, and it seemed to change everything for my reading life. Because that book grew in popularity, and eventually got turned into a film, I soon found more books coming out that revolved around characters that weren't straight.
A lot of them were coming out stories, which were amazing. The film "Love Simon" (based on Albertalli's book) is the first coming out story I can think of when it comes to mainstream books and/or movies. "Love Simon" came out last year, my second year of college. One of my friends didn't come out as gay until a couple years ago. He told me that "Love Simon" was the movie he wished he had in high school because he saw a part of himself in Simon that he didn't get to see in a lot of other characters. And Simon was a fully developed character, not a stereotypical "gay best friend."
As I kept reading, I found more and more stories that weren't just coming out stories, because just because someone's sexuality isn't their whole character. A year ago I read "Radio Silence" by Alice Oseman. The main character Frances is bisexual, but that wasn't the focus of the story, it just happened to be a part of who she was. Heck, you didn't even find out what she was bi until about halfway through the book when she tells her best friend, and it didn't become the central focus (they were too busy making a Youtube podcast and dealing with a psychotic mom).
Then I found stories with a representation of even more sexualities, pansexual, asexual and demisexual. I've even found books with gender queer and trans characters, which are amazing. I've had friends who have come out and finding stories that they can find themselves in makes me happy for them.
LGBTQIA representation has improved so much, at least from my point of view, over the past five years, and I want it to keep getting better.