Having no way to come to terms with his trauma, and being forcibly calmed rather than persuaded during relapses, my neutral character is progressively becoming more evil.

To be fair, the idea of “confronting” or “working out” certain feelings, such as trauma, can actually be worse for you. Studies show that if you have newly traumatized people playing buttloads of Tetris, they might be better off, with fewer intrusive memories. Also, more colloquially, “confronting” feelings can also be a way to rationalize ruminating over negative crap, which isn’t good either.

I would say that using calm emotions in this context isn’t a quick fix, but it means the traumatized character can be more rational when dealing with what she feels; stuff that was just too much for her before isn’t as much now.