So you are both trying to convert each other and have a friendship based on agendas. Well, you both know it so if it's what you choose to do, it's what you choose to do.
I'm not straight but I don't try to change people's minds about it. If they say they don't understand it, and they seem actually open to listening, then I might talk about it.
I personally don't like making people my project.
If she is one with it and you are ok with it, then continue to dialogue.
But don't stop there.
The level of ruminating you are engaged in about why why why, even when you have been given very real enable and fully adequate why answers form her and other here, is really about you.
Why do you need to dissect this more? Why isn't the reason she has given enough of a reason?
What is it about Her explaination that is such an unacceptable answer to you?
What would be enough of an explaination for her answer?
It is a good dialogue but I think you are getting push back because you take it so far. What if someone asked you why don't you like to have heterosexual sex? And you gave an answer and the other person kept saying yeah, that's part of the reason, but what are the others? Why? And what if they did his with the agenda to try and convince you that being gay was wrong - something you don't agree with.
Do you see how invalidating that can be? It's not that much different than what you are doing with her.
The why's are going to make this ok and ignoring the reasons given aren't going to help you convert her.
I know someone who is a racist. I don't like it I don't support it and we dialouge about it. I know that he had very awful experiences with people of a race and he bought into political ideas that encouraged him to scapegoat a race even more. Knowing all the detailed whys as to how be became a racists doesn't make his racism ok. It allows me to not get so shaken by it, but it doesn't even change how I respond. I just be the good person that I am and I invite him to know others of other races and have different experiences. It's his choice to change his views or not. Not up to me.
And before anyone thinks otherwise, I'm on your side, and I also know what it's like to be on her side and have people approach me as a project, as someone to change, as someone they needed to dissect and understand all the whys and it didn't help me change my viewpoint one bit.
Safe relationships where people held boundaries, accepted me for who I was, and spoke the truth as they saw it in a kind way, and without an agenda --- these people changed my entire being and helped me heal more than all those who tried to change me.