He is pissed that his daughter is losing big time and President Trump did not support her.
This past week alone has been a colossal disaster for RINOS as MAGA candidates utterly dominated the various primaries with the Kari Lake victory in AZ being the cherry on top that delivered a debilitating kick in the stomach to the RINO crowd who honestly thought they had Trump destroyed forever with the 2020 election steal and the J6 frame-up.
Trump and MAGA are back stronger than ever and in a few weeks, Liz Cheney will get her death blow in Wyoming. So yes, the Cheneys are angry, but mostly just scared.