They all betrayed him. Any one of the disciples could have done any number of things to take their stand with jesus.
But jesus had to go it alone. Because his goal was to fulfill what was promised, that the stone the builders reject becomes the chief cornerstone.
Just as YHVH said to Samuel, "it is not you the people hVe rejected, but me."
Because the people wanted their puppet king, the way of the rest of the world, and the got it.
Jesus fulfilled his role as prophet king by becoming the crucified suffering servant, to show that God, the Lord of all creation, is the lamb that was slain from before the foundation of the universe who's life is given for the life of all.