I am concerned with the number of posters who suggest that @Shazboo should leave dealing with their DS to her husband; this is reminiscent of "wait till your father gets home" and will only increase her DS's lack of respect. It would be better for Shazboo to tell her son that she will not accept this behaviour and for her husband to support her to do this, rather than take over; to "amplify" rather than take over. In this way she is sending DS a message that she will no longer put up with being treated badly. I would suggest going into this meeting having some ideas of what the basic "house rules" should be and from there negotiate. If this seems too difficult then perhaps a mediation service? They may not be available in person until after the Covid crisis is over but worth a try. If all else fails then I'm afraid telling him to leave may be the only way to elicit change.
Obviously, if you think he's suffering emotionally then encourage him to see a doctor/counselling service.
Shingles - Again. Have the Vaccine!
Passports not in the drawer I always keep them in. Turning the place upside down.