Since we've been heading here all season -- and nobody in this entire episode is actually having the conversation they think they're having -- Lip assumes it's because he broke their cardinal rule of being sluts together, and grabs her face: "I don't love you. That wasn't love you-love you, that was like middle-of-sex, you know, love you. Listen, honest! I don't love you. Okay? No, listen. I promise! I promise, I don't love you!" All the way up the stairs, with him still in his boxers begging, calling out the precise opposite of the truth: "Karen! Karen, I don't love you!"
Which I mean, for a show called Shameless I think Karen's the only thing we're really ending well on. What a horrible fucking situation. Doesn't it seem kind of familiar, like high school? You're not allowed to love anybody, because that's too needy, but you want everybody to like you, so you have to fuck them without loving them, suck off their gay brothers and have orgies and whatever, make out with other boys in front of them so they won't go away.
And you've got your dad telling you he'll love you if you only admit that you're a whore, and then like a jack-in-the-box clown, surprise! That's the one thing he can't forgive. He takes the shame in him and he puts it in you, and then blames you for it.
Jasmine: "I like you, Miss Fiona. You're a dirty girl like me."
Lip:"I promise, I don't love you."
And you've got Daddy Frank at just the wrong time, offering you the chance to finally win one because he's someone that is not worthy of any kind of need. Nobody will ever care to win his approval, or his love, except for Debbie and Carl because they don't know better yet. Because he is the lowest. Daddy Frank, who's so insecure about his own masculinity he's just waiting for a reason to headbutt Ian, or fuck Lip's girlfriend. Who would rather put his back into a speech about the strength of character it takes not to do those things than it would take to simply not do those things.
And at the heart of it, this amazing boy who's so afraid of scaring you off that he's willing to do anything for you, to you, to prove he's just as hard as you are: And that's the only person you've actually hurt. All that time saying you weren't mad and it turns out it didn't matter if you were. It wasn't about anger at all, it was about spreading the shame so wide that nobody could get away.