You know, considering everything, you'd think Faye would be more angry at Sven than Gina.
Clearly, you have never been cheated on. And for that, I salute you - you are lucky, lucky, lucky for that lack of experience.
Unfortunately, that's how the human mind works. When something like this happens, you're initially angry at the person you love, but then you're even SO MUCH MORE INCREDIBLY angry at the person they cheated on you with. You generally don't want to physically hurt someone you love, even though they hurt you. But the person they cheated with... you want to rip their still beating heart out of their chest, fill it with gasoline, stick it back in their chest so it pumps that gasoline through every single vein in their body, make them swallow a match so the fire rips through vessel and capillary alike, and
then give them an IV drip of napalm, so that system-wide blaze won't go out for a good looooong time.
Not that I'm speaking from personal experience or anything...
But my guess is that it's the love that you feel for the person that keeps them from being the main focus of violence. The anger is there but... I dunno, it's just not the way it works, for some reason. You want your SO to hurt emotionally the way you do, you want them to cry and feel guilty and ashamed, you want them to beg and grovel to hope to be worthy enough to one day be worthy of being in your presence... but if you destryoed them, they wouldn't be there anymore, and you don't want that. You don't have an emotional connection to the one they cheated with, so there's nothing keeping you from releasing the rage you feel toward them.