Episodio 08 Stagione 12 "Semper Fortis", "Congedo Mortale"

Sean Murray of NCIS tweeted that fans would find out why McGee is acting like he isn’t over Abby, if he still loves her. Can you confirm what episode this will be touched on? —Robert
I can confirm that Murray was alluding to this Tuesday‘s episode (CBS, 8.7c), in which McAbby have what I am told is “a very personal conversation.”