You're not saying he was diagnosed with this by a qualified physician/therapist. Is he self-diagnosed? If so, he's hiding behind a label.

You don't need to be "empathetic and understanding" here. You should be running for the hills because as long as he's going on work trips he will probably always be acting out.

No legal entanglement here - cut your losses and move on. No contact = no new hurt. This is like a car with 1 wheel - it'll never really drive right.