But if you look at Witcher 1 dialogues, Geralt also remembers feelings for Triss specifically. First there is "I feel like you were important to me" when he arrives in the courtyard, then an exact repetition of sentiments from Blood of Elves: "I've not had many reasons to be happy of late and the feelings I experienced on hearing that you lived cannot compare to any other. Except perhaps what I feel now when I look at you."
So Geralt is confused about loving a sorceress, but not about caring for Triss. The happiness he feels seeing her is the same as in the past. He doesn't start to love Triss because he thinks she is Yen; he starts to love her because that is what would have happened if Yen had not been in his mind the previous time.
Cause it's true, Geralt really loved Triss in the books. Loved with....brotherly love.
People can interpretate 2+2 like they want (I see they like it) but I think it's hard to ignore the fact that Geralt cared about Triss like brother cares about his sister.
The reason Geralt slept with Triss at first time - the same as for everyone, trying to replace Yennefer. He honestly sometimes didn't really care about with whom he sleeps - a hooker, a sorceress, a medic. Everything just to forget the world for a moment and imagine himself with Yennefer. It doesn't make Triss special. We can say thay he loved Fringilla too. So Fringie is an only true love?
In "Blood of Elves" Geralt prioritizes pretty clear - whom he loves like a woman and whom he loves like a sister.
Triss tries to seduce him in Kaer Morhen when he's not with Yennefer so literally he could sleep with anyone he wants like he used to but says no to Triss.
Of course you always can blame the wish but dat wish never was an obstacle to sleep with another women.
He cares about Triss but he doesn't want her. Kinda Foltest in reverse.
The same in the game. She seduces him but when he remembers everything he leaves her again.
Ofc course it's hard when you just've slept with woman who was like a sister for you but Geralt knows better, right?
In TW3 it's pretty clear how Geralt acts with Triss (only if you don't click the buttons with "luvluvluvluvyouTrissy"). He cares, he helps and that's all.
Also he feels some guilty for their relationship transformed to something more than brotherly love but it's not his fault.
"BUT SHE LOVES GERALT!" is not an argument. Fringilla loved Geralt, Essi loved Geralt, Shanni loved Geralt. Pity them all?
And good for Triss she finally found a strength to face it.