If you replace the 'fat girl' references in the monologue with the words 'crippled guy', Louis CK may well have recreated the transcripts from all my moments of emotional devastation.
You know what the meanest thing is you can say to a crippled guy? "It doesn't matter that you can't walk." I mean, come on, buddy. It just sucks. It really really sucks. You have no idea. And the worst part is, I'm not even supposed to do this. Tell anyone how bad it sucks, because it's too much for people... But if I say it, they call the suicide hotline on me.
I mean, can I just say it? I'm crippled. It sucks to be a crippled guy. Can people just let me say it? It sucks. It really sucks. And I'm going to go ahead and say it. It's your fault... Why do you hate us so much? What is it about the basics of human happiness, feeling attractive, feeling loved, having girls chase after us, that's just not in the cards for us? Nope. Not for us.
How is that fair? And why am I supposed to just accept it?
And on it goes. Every line, every pause, every juxtaposition is like an auteur's gut punch. Because yes, I have given that speech, (or at least some version of that speech) at least 25 times. And Louie's character being Louie's character, knows that the only way to end this discomfort that he's feeling at the end of Vanessa's monologue is to take Vanessa by the hand and get her to shut up, so he doesn't have to think about how uncomfortable he is any longer.
I imagine the laymen's interpretation of this scene's ending is that it offers a pleasent, if unsatisfying conclusion as Louie takes Vanessa by the hand and tells her the 'So The Fat Lady' joke, as they walk off into the distance. I, on the other hand, perceive it differently. There is no acknowledgement that Vanessa's words have sunken in at any point, rather that Louie is pleased that he withstood the tirade.
I believe this is intentional on the part of Louis CK, the writer. He knows that Vanessa's 'rant' makes the viewer uncomfortable. and he acknowledges this by contrasting it to his own body issues earlier in the episode. He knows that crippled guys and fat girls fight bigetory everyday, and yet we are, and will continue to be, powerless to do anything about it.
The guys will always lust after the skinny girls, and the girls will always think that 'crippled guys' are too difficult and damaged.