Agreed. That's not fair to Beverly.
But I think the problem was, the show would not have Beverly simply admit it.
She could simply say she wasn't attracted to females. But maybe the fear was that by saying that it would hurt that perfect image of human beings in the 24th century.
So she has to reject her, but make it about changing different bodies instead of her gender.
Even though she slept with Riker when he was the host and seemed eager to meet the next host when she thought it would be a male.
The explanation had a 'have your cake and eat it too' aspect to it.
That's the irony right now. Would Trek Picard boldly just say Seven was bi or had a female lover, or just leave subtle hints about it.
I do not read the situation quite that way. Beverly needed to be convinced by Troi in the first place than Odan-in-Riker was still close to the same person than she had fallen in love with, and even then it took time.
Three different hosts in the space of a week would be dizzying for anyone. That the third host was a woman, I think, underlined for Beverly just how little control she had over even basic elements of her relationship.
Since she was just using Seven going by what was said, anything jiggy with B'Sassy would have been one sided and toxic. I can buy them having sex but I'd never buy they were lovers in the sense of an honest or equal relationship.
That's the fun of ambiguous scenes like that. It's fantastic fodder for creating backstory fanfics of all kinds.
I think we can agree that an ex who wants to vivisect you for your body parts, and does this to your foster son, is a bad ex. That Seven has had so little experience surely did not help her.