It is good to be working on a case, even if the case happens to be deeply personal at this point. At very least the plane incident doesn't directly relate to her and Ted, so she can at least mostly decouple her personal feelings from it. (Not that they haven't done personal cases...they certainly have. It's just a little less stressful this way.)

She smiles fondly back at Ted. Sherlock comes to sit next to her again, and she mouths "love you" before turning back to the documents.