She loves how happily surprised he is, how much joy he gets from being with her, from being kissed by her. She beams up at him, her arms still loosely around his neck.

"You're amazing," she says. "And I'm just so lucky to be with you."

With everyone else, Sherlock has a barrier. Joan loves Sherlock, so when the people she's seen inevitably hate him, she's wound up feeling conflicted, unhappy with Sherlock, unhappy with her date, unhappy with her life. It's one of the many reasons she's avoided getting romantically involved. But it's not like that with Ted, and she's just so happy and relieved and proud.