On the one hand I don't think she got over it so much as the problem went away when Buffy gave up on bonding with the SiTs. On the other I think her issues with Buffy (and she's only whiny with her, seems pretty relaxed with Willow and Xander) are subtly different. It's not that she wants to be part of Buffy's life but that she's starting to have her own and wants Buffy to be interested. More like Willow in DMP having all that scary life stuff she was going through and no-one to talk to or at least not the person that she wanted to to listen.