Corbyn must be gutted. He led quite the long chant of "Free, Free Palestine" as he was announcing the Your Party launch.
It's not enough to roughly know where you are on the political spectrum and vote accordingly. Now, you have to check which bit of them is just ahead in their internal back stabbing contest. That makes quite a difference in broad parties.
Then you have to check to make sure the people you thought you were voting for haven't formed a new party or defected to another one. Then check to see which fringe outcasts and hate mongers have been infiltrating your party of choice, and see what they're likely to get away with, in all the in fighting and possible coalitions ahead.
All for the privilege of being disappointed by their conduct, ability and delivery of anything except failure.