Layla was first to react to the news of Serena breaking the engagement with her brother.
She was so fuming with anger, She was so pissed off that she even lashed out with not so pretty words towards Serena in her comically childhood voice.
But then quickly realised that Max can turn blind eye to most things but even single words against that woman make him go scorch earth. He can tear face off with anyone.
He is still not talking with their mom just because mom said Serena is not right for him. That one sentence was enough for him to say mom is dead to him.
It's been 8 years, mom tried each and every way to ask for his forgiveness, make him talk to her yet he did not even acknowledge her presence much less forgive her and talk to her.
Hence why the moment she wanted to call Serena bitch, her heart became cold as she quickly try to save it.