[ Derek didn't think Tate was shallow. He understands that sometimes people just - drift, or change, and that kids Tate's age can become different fucking people at the drop of a hat. For someone who's been dead for as long as Tate has, for someone who seems to struggle against the stagnation of their own growth, he feels like it wouldn't be too much of a surprise, if he and Peter had gone in different directions and grown apart. Tate moving on to Sabrina is no different to Scott moving on to Kira.

But - well - his opinion does get a little colored when Tate gets defensive. It's kind of a childish reaction, which makes him look shallow in a way that he hadn't before - like he's mad at Derek for suggesting there's something wrong with forward momentum, because he was in love and Derek just couldn't understand, or something. He adjusts his approach to this conversation, a little, looking out over the woods rather than at Tate directly. ]

... Well, who knows. You said something about how - people never really go home, right? Maybe he's just stuck in a freezer somewhere and we'll be able to get him out one day.