Internalized homophobia (or internalized sexism or internalized transphobia, etc.) is something that we don't talk about enough in the queer community. I can't think of a better way to explain how and why it's a problem than through telling my own story.
Please remember that this is my story and I didn't decide who got to be in it, so don't think that I left any group or issue out. I only went into detail regarding stuff that's important to my story. Other people's stories are not mine to share.
I always knew that I was different, but I didn't know what made me feel different. No one gave me permission to be gay. It didn't even feel like an option until I was in high school and met actual non-closeted queer people. Even after I knew it was possible, it took me a long time to admit to myself that I found girls attractive. When I was a college freshman, I settled on calling myself pansexual/bisexual and it wasn't until my junior year that I even allowed myself to think that I might just be straight-up gay.
One of the biggest problems— one that most queer kids experience— is that no one ever asked me what person I had a crush on. They asked me which boy I had a crush on. I remember hating that question. I got teased and was pressured if I couldn't come up with one, so I started to pick shy, feminine guys— guys that part of me knew I was unlikely to get anywhere with.
Eventually, that was second nature to me and I did it automatically. I didn't go from "boyfriend" to "boyfriend" like everyone else did; I went from crush to crush. The crushes were very shallow and lasted for a long time. I think they were just armor that I hid behind, so that I didn't have to say that I didn't have a crush. I also did it for the imaginary flirting and the idea of actually of "dating" them (this was K-12), but I'm not sure that I ever actually wanted to. I figured I was just shy and would grow out of that.
Looking back, there are a lot of things that I might have noticed if I had known that there were other options. I didn't go crazy over any famous guy that I can remember at all, "The Notebook" didn't phase me, and I liked Cinderella, but I didn't particularly want my own knight in shining armor— I wanted to be like Mulan.
My favorite shows, the ones that I remember the most clearly, were "Kim Possible," "That's So Raven," and "Lizzie McGuire." They had strong female leads and weren't focused on couples. Yeah, Lizzie and Kim each had constant love interests, but they were both minor characters in comparison to their female counterparts. That was the closest that I could get to queer characters and I had no idea that I even wanted to see queer characters!
I was told that, by wearing makeup and certain clothes, I was "trying to impress boys," but that was never it for a great number of girls of all orientations. It's like these people forget that queer women and all kinds of men wear makeup! Even teen magazines for girls were hyper-focused on impressing your (male) crush, etc.
One of my personal "oh, sh*t!" moments was when something on the Internet pointed out that lots of queer people, whether they did it on purpose or not, present in ways that deviate from the heteronormative image of the ideal human that is forced upon us all. I dye my (short) hair all colors, I don't shave, I don't wear makeup— or anything else— the way that I was told that I'm "supposed to," unless I actually want to (which isn't all that often). No one can touch me if all they have to do is look at me and realize that I don't care what they think, that I don't want to adhere to any norms.
I know, I know. There are probably straight girls that had the same experiences, but there were no queer shows, role models or literally anything else available to me, if they even existed at all, and that was my personal experience.
By the time that I found out that gay women exist, I had already internalized homophobia so much that I genuinely thought I liked men. From the time I first chose the label pansexual and tried to be part of the queer community, I knew that I was welcome and had a right to be there, but I had this looming sense of guilt, fear and general discomfort.
Something wasn't right. All I knew was it didn't "feel" right for me to like men and be in this community. It frequently crossed my mind that I seemed to be more into men than women and I didn't know why, it didn't feel right. Now, I know that I hadn't given myself permission to even consider the idea that I might not like men.
The world had told me that being gay was a sin and that being straight was the norm. It was so much easier to like men, even if I also liked women. That way, I could choose to be with the (binary) gender that I was "supposed" to be with. I wouldn't have to explain anything to anyone. I wouldn't have to deal with all of the hatred. I could just be "normal." I fell for it— I tried really hard to like men. I tried dating them.
Well, world, I'm sorry, but I am a lesbian.
The point of telling this story is to point out that internalized homophobia can hit you when you least expect it and also to shine a light on how big of a problem it actually is.
It doesn't matter how old you get or how "out" you are. You're always one "oh, sh*t!" moment away from discovering yet another thing that you were lying to yourself about.