This ask has a bit of canon divergence I hope that’s ok. How would Karren feel after finding out her once human s/o is now an artificial ghoul and therefore has a shorter lifespan due to their refusal to stop fighting for goat

Oh, she would haul their ass straight up to the Tsukiyama mansion, force them to sit down, and give them a long, details, persuasive lecture. 

If they are still determined to fight for Goat, that’s fine. She’ll join them and completely defeat their enemies for them so they don’t use their kagune and hasten their death.

Or.

She’ll surreptitiously start looking for peaceful solutions.

Karren ain’t accepting this without serious efforts against.