nm I googled it
[quote=someone on Quora who is suspiciously knowledgeable about petty alt. right politics]
Q: Why don't Ben Shapiro and Milo Yiannopoulos get along?
A: The Michelle Fields incident triggered the fallout, though it may have occurred eventually anyway.
Shapiro, a Cruz supporter, sided with Fields after the alleged assault on her by Corey Lewandowski, Trump’s campaign manager at the time. Shapiro resigned his position as editor-at-large at Breitbart, decrying Breitbart for their lack of loyalty and ethics and calling out Trump’s camp for what he thought (still thinks) was an assault. Milo, a Trump supporter, sided with Breitbart.
In the aftermath, Shapiro has become something of a whipping boy of the alt-right. Even though Shapiro is as conservative as they come, he's anti-Trump, which makes him the equivalent of a Hillary supporter to many in the young Trump camp. Shapiro has thus been pinned against Milo, one of the most prominent figures of the alt right.
[/quote]
https://www.quora.com/Why-dont-Ben-Shapiro-and-Milo-Yiannopoulos-get-along