Your H is going monster. You've got to be really careful in your responses. Remember to validate his emotions, that's the best way to diffuse altercations. Maybe a more appropriate response would be this:
"H: Hey- FYI-I turned off Ds phone just now for 3 days for her disrespectful attitude"
"You sound angry and frustrated with her, I'm sorry you feel that way. She's angry and frustrated too, perhaps the two of you could talk on the phone about it. You know how sometimes a lot gets lost in the translation in texting, a phone call might work better."
You're not agreeing or disagreeing with his position and his cutting her phone off, you're just validating his emotions and suggesting a possible way for them to make amends with each other without you getting in the middle of it. You're also not taking sides.
