She really is.

She's juggling the twin pressures of dealing with Cadsuane (an arrogant, hard-nosed bitch) and being perhaps the only person that Rand is willing to listen to. Between that, and dealing with Rand offhandedly mentioning he might let her husband be slaughtered, and all the rest of it, I think she's handled herself remarkably well.

Like, with the Lan thing. Egwene would have shouted at him, called him a woolhead, then gone off to gossip about him with the Aiel. Cadsuane would have slapped him. Nynaeve, who I honestly couldn't blame if she had leapt for Rand's throat, instead controlled herself, and despite being horrified/shocked and trying to convince Rand, made sure that she could stay by his side and perhaps slowly turn him away from the monster he was becoming.