Kitty Pong?
I know her character is presented as over the top for a reason but let's be honest here. No man is going to bring her to a major family event much less consider marrying her.
Then they show Bernard with 4 drop dead gorgeous girls, 2 on each side of him and he immediately wants her? Get serious.
She would be somebody you screw on the side not have a serious relationship with. I do not mean that top be sexist but it is true. Alistair is not even married so he can do what he wants.
They show Kitty being nice to Rachel to soften your views of her but she should not even be there.