Just had to get something off my chest that doesn't make a lot of sense to me. It relates to hotwives / cheaters / etc always having this thing about not being with anything that doesn't resemble a wiffle ball bat.
This is my take on it.
Humiliating someone because of his size is easy because it never fucks with his head. He can't grow a bigger dick but he can be smarter, wittier, better talker, etc. If she's really looking to humiliate her boyfriend, she needs to fuck anyone BUT him. It gets a bit more complicated past that. Say for example, she rarely gives head. She needs to find a guy and become his blowjob bitch. All she does is suck his dick, just never fucks him. He gets to cum anywhere he wants, bonus points for facials if he's getting home soon. So she doesn't like anal. She has a fuck buddy or two that regularly fucks her in the ass, two or three times a month. Leaves loads in her ass so he can see it leaking out when she gets home. Lastly she has a couple fuck buddies. They have open standing to come and fuck her. Works even better if he gets her started with foreplay or going down on her and she calls one of them or has it prearranged for the other man to come over and fuck her. He is either forced to watch or has to leave the room. If he's watching or listening, she gets very vocal with how much better the other guy is. His cum tastes better. His dick feels better ( even better if he's the same size ). He fucks me in the ass like he owns it and you're not enough of a man to. Size is the easy way to humiliation. Moving into the mental territory is where the true humiliation is.