You’re the Worst 10 p.m., FXX

Last season, this enjoyable and intelligent comedy got dark, as we learned that Gretchen, one half of the show’s Beatrice-Benedict pairing, had been dealing with clinical depression.

In retrospect, the diagnosis seemed inevitable, as Gretchen was in the habit of numbing herself with drugs and — thanks to the wonderfully acerbic performance by Aya Cash — she was also forever tumbling into nihilistic rabbit holes.

The theme continues as “You’re the Worst’’ returns for season three, and that’s a good thing. First, it signals that show creator Stephen Falk didn’t use depression as a plot gimmick; he appears to understand that it is often a long-term struggle. Second, Gretchen’s depression adds poignancy to her relationship with Jimmy, since they’ve managed to survive it despite their mutual cynicism about relationships.

And finally, it has resulted in the casting of Samira Wiley, one of my favorites from “Orange Is the New Black,’’ as Gretchen’s therapist.

I love the Gretchen-Jimmy material. They both have regular impulses to leave the relationship — and yet that shared instinct to run gives them a lot to bond over. It’s oddly endearing.

I like but don’t love the supporting characters. They’re fine, but they also feel a bit like missed opportunities. Edgar, played very much — too much — like Ross on “Friends’’ by Desmin Borges, doesn’t quite seem believable as a guy who has PTSD after having served in Iraq. This season, he deals with his sexual impotency. And Kether Donohue is funny as the wacky friend who wants what she doesn’t have, and doesn’t want what she has. But a little of her goes a long way, as she plays out the same joke repeatedly.

Still, the return of “You’re the Worst’’ is a welcome event, a great way to fill in some of the TV dead zone between now and the mid-September rush.

Matthew Gilbert can be reached at gilbert@globe.com. Follow him on Twitter @MatthewGilbert.