What was wrong with Tyler? He seemed like a fine fellow. Did he cheat on her?
Although I don't necessarily condone cheating, I can't say someone is a horrible human being for doing it.
It highly depends on the situation, and all we can do is speculate. Maybe Frivvi is unsatisfactory behind the scenes and Tyler just wanted to release his explosions inside another woman's orifices while still maintaining the relationship he had with Frivvi?
As a polyamorous individual, I regularly encourage people to at least entertain the idea of having a committed relationship, but also have sexual intercourse with other partners in a healthy way.
If he did cheat and that displeased her, Idk if that's a good enough reason to call it quits. If it were me, I would stay together and try to understand the situation. It's totally possible they could've rekindled their relationship by agreeing to orgies. I think orgies are a great way to strengthen the bond of your committed partner. You discover more about each other in that type of environment.
For example, I had an orgy with my committed partner and it simply made me love them even more, I barely wanted to suck other female tits and insert my penile erection inside other female orifices. All the extra people making love around us just added to the intensity of the moment my partner and I were having. Hearing other peoples' moans put me in an ASMR-like trance. It didn't distract me from my partner, but added to the experience.
If they aren't comfortable with orgies, that's fine, but I would encourage monogamous people to enter the brain space of polyamorous individuals, regardless.
Maybe there's still hope for Frivvi and Tyler getting back together?
If it was her decision and didn't cheat though, then maybe they were simply incompatible in a general sense.