And that's it really. Stella tells Stolas that she "tortures him" to remind him of what he did; the cheating. And Stolas feels no remorse for what he did to Stella. He says "I would feel bad if I hurt you, but we both know I didn't do that." Bitch, yes you did hurt her, whether it was her emotions and/or her public standing. What, because she wasn't crying? You do know that people also respond in anger when they feel hurt? That's what Blitzø did when you cut him off. But you're to wrapped up in your own emotions to notice.
Hell, he doesn't even think what he did qualified as cheating. He has little to no respect for Stella. Why should she?