Rosie: When you get your Master's Degree.note Given the amount of study required for such a degree, Rosie is saying that Izzy can't have sex until she's at least 22.
Izzy tries to haggle it down to fifteen. Rosie relents and says seventeen is okay. Izzy responds "fifteen is the new seventeen."
When Izzy and Rosie are playing with the Barbies, the scenario is a Soap Opera esque wedding interruption. Rosie gets uncomfortable because Izzy has her 'character' insult the other's fashion sense - so she backtracks and tries to change the scenario to them making friends.
Izzy: Why is she suddenly being nice?
Rosie: She's manic depressive.
Rosie's ex-husband asks her if she has any dates. When she replies in the negative, he says completely seriously "you have got to get over me already."
Rosie thinks Adam is cheating on her and Nathan walks in, casually talking about how one knows when Rosie is really mad - as her voice gets high-pitched. Which it has.
Nathan: After my Bachelor Party, only dogs could hear her.
Rosie: I am not Demi! You are not Ashton! And YOU! [points at Nathan] You are definitely not Bruce Willis!
When Rosie discovers that Izzy and Mel crank called various celebrities, Rosie starts falling apart. Izzy suggests her own punishment: writing an apology letter to everyone she called and not using the phone for a week. Rosie changes it to one month, but Izzy advises "that's excessive; two weeks" and Rosie agrees.