It’s a bit difficult to say, but on balance I’d say…for all intents and purposes, no.
It’s not as if we got a traditional “break-up” scene, but Adalind did leave him and doesn’t appear to have any plans to return to him any time soon. Add to that the fact that they’re both pretty wrapped up in surviving their respective situations, and somehow I think their relationship status is probably so far down their priority ladder that it’s fallen off the bottom rung.
If or when they actually have the time and space to revisit that question again, a lot of things will have changed. Juliette is back, and it’s clear from Nick’s behavior toward her that he hasn’t moved past his feelings for her, as tangled and convoluted as they may be by what happened last season. And Adalind now has a daughter who’s shown something of a volatile streak towards people who aren’t either of her parents trying to date either of her parents.
Granted, she didn’t seem to have a problem with Nick toward the end of that episode (and may have even acted to save him and not just to punish Conrad for hurting Adalind). But still…that might change if she were to see Adalind and Nick together, especially if the first thing Nick does in season six is go all decapitare on her dad.
So basically, it’s complicated. But for the moment? No, they’re not.