My only comment is that hopefully Sweetie can realize that he isn't the cause of yours and Hubby's issues- they existed LONG before you met Sweetie. Nor is he the cause of your Hubby suddenly (and unilaterally) deciding that what has been the agreement for a couple decades is no longer acceptable.
I know a relationship without the physical aspect can be difficult, but it can be managed if you both want to do that. The fact that you are long distance may help- you will have far fewer temptations.
If I were you I would ask Hubby whether he plans on getting back on a place where your previous agreement holds. If he says "no", then you will need to decide if you're willing to stay with him. If he says "yes" then some sort of time frame needs to be established, with "milestones" that can be accomplished to show that he really is working on his issues and not just stringing you along.
I wish you luck!
Pan Female, Hinge in a V between my mono (straight) husband, Monochrome and my poly (pan) partner, ThatGuyInBlack