Greytail's Depression

"Why must I, the useless elder, survive if she didn't? Answer that, oh wise one."

Greytail, a headstrong senior warrior, has been serving his clan for long since he can remember. He finally has a beautiful mate and his sister is suckling kits. Things are finally starting to look up for him, but a clan meeting is called and his world goes spiraling downhill. He is sucked into a world where you almost never go outside of camp and you constantly count the days you have left.

What will happen to Greytail when he is falling into depression?