This happened about 10 months ago. C & S very early talked this over, and it's been a long time since things have been normalized between them. Let bygones be bygones. The relationship between Clara and Stas has been stronger and stronger with time, T & Z were guests at Clara's birthday party, the 2 couples meet regularly, etc.
Personnaly I don't see the point of endlessly bringing this up like a Scarlet Letter every time they are in the same room, the only consequence of this being to potentially revive old wounds and pointlessly hurt everybody there. Just my opinion.