Why is Griffith crying at the end of Episode 364?

Episode 364 not only was the last chapter Kentaro Miura (may the Gods bless him) worked on, it also left with a cliffhanger that may have felt like a punch to the face for some. Particularly the last page of Griffith crying may be very confusing.

Luca: Good People aren’t always Good Parents

You know what's really fascinating? The different roles Luca & Casca play in Nina's life. Luca is determined and always seems to know what is there to do, while Casca has no will on her own. Nina makes an important realization dealing with our regressed former commander of the Band of the Hawk.