I suppose you could bring him to therapy with you, one time, maybe your therapist would be willing to try to help explain it to him. But ... well maybe I'm to old to remember LOL! how dense teenage boys can be - it just seems like if you've told him how you felt and he knows what you've just been through he would have "got it" already. But talk with your therapist, if you feel you want to, and see what s/he says about it.