She's a wound up individual caught up in some major politics, I'd a bit of a dick too. :P

She always did seem like a jerk to me in the books as well. I can't understand why he loves her.

Priscilla's song (The Wolven Storm) might hold an answer for you. ^^
But I don't know, somehow they both fit together in the books. Even as Ciris parents.
When I met her in the game I really wondered why she is so cold to Geralt... she must have known how desperately he searched for her. And when beeing in the palace, they surely would have been able to take some private time. Their connection was no secret so even if the walls have ears they could still have talked a bit and/or have sex after not having seen each other for so long.
I guess Ciri means more to Yen than Geralt because Yen is a woman and Ciri the child she can never really have but she always wanted.


And on top of that, the devs said they are going to improve the Triss romance but it will take some time and I don't want to only experience the inferior, current version. =/ But I don't want to force myself to not choose her and instead choose her in the second playthrough, because I want to experience the game with the choices I actually want to make.