Not only had Ariel survived the attack on her. She was now back home. and she was recovering. The recovery process was slow, but it was still progress at the end of the day. So Tristan was happy.
When she had been in the hospital, Tristan had had this thought in his mind, where he had believed that he would never ever leave her side again, that the two of them would always be in touching distance of one another so that he could keep her safe no matter what. But now, Ariel was out of the hospital and reality was slowly sinking in for Tristan. When he had wanted to work from home so that he could be closer to her, Ariel had insisted that he go back to headquarters, that the employees needed to see him in order to be reassured that all was well.