[@Raineh Daze]If he DOES care, he won't show it in front of others. His comment about being unable to fathom Johanna's threat was because Estelle is her enemy and it would be solely to her advantage if he [i]did[/i] abandon her.

Also, not sure if Rider could've really done anything to help Mira even if he'd stayed, but he'll be pissed if Saber gets taken out of the war in such a "cowardly" way.