I discussed this kind of thing in a paper I wrote recently. Once you finish your work and the book is in the reader’s hands, it’s up to them to complete the story. The reader/audience is the last piece of the puzzle and you can’t control it. Their understanding of the story is what they’re gonna take away from it and your job is to influence their understanding as best as you can. What you intend is never going to be exactly what they take away, and that’s just how storytelling goes
It’s important that you’re thinking about going about doing this in the right way but if people are upset about her ending up with a man then they are literally the problem and are contributing to harmful narratives surrounding bi women, so I don’t think that’s something you need to cater to