I guess half the story just doesn't exist then. No there was no story about a boy discovering and coming to terms with his sexuality and learning to love someone for who they are on the inside. Absolutely not. Didn't exist.
You're right, it doesn't exist, because the story was never about one's sexuality and romance. I think you're confusing sexual identity and gender identity.
At it's core it was a story about a trans boy and his journey to acceptance
Rika is transgender, meaning he isn't the gender he was born as. Rika's story was about coming to terms with himself and finding people who accept him. Never was it about romance, and honestly I don't remember him ever bringing up the topic of his sexuality.
While there were romantic elements, the story was never a romance.
Satsuki's story was about him finding people who appreciate him and lowering his walls. Which did end up with him falling for Rika, but in the end he decided to not push it because he wasn't completely sure what these feeling meant in regards to how he see's Rika, and wanted to keep being Rika's friend.
I can agree with the story having a rushed ending, and overall how Satsuki's story wasn't really resolved, but you're getting disappointed over something that never existed. The story was always about two kids accepting themselves and trusting those around them, and really, there was never a hint of anything romantic going on between them until Satsuki realized he had feelings for Rika.