I am so glad you got away on holiday. Teens are rubbish company but you got sunshine and you were there for them, even if all they wanted was pocket money and food. I think that matters: they know you are emotionally available to them and present, even if what they need is space and privacy. You are giving them that and they will remember it and it will lay the foundations for your adult relationship with them. (I hope this is true for me too, as the owner of a sulky teen myself...).
Your H sounds like terrible company. At least you only have to have it in small doses, and you don't have to live inside that head of his. I think withdrawing the wife-admin and letting him do his own car insurance is a great move. I remember you paying his rent for him and being aghast at that. I think you withdrawing the emotional support is probably a good move too. I know we're taught to validate, but I think with men like your H (and mine, when he is in that mood) too much of it lets them sit in their self pity, festering and whinging. If you can do it as a kindness without cost to yourself, well fine - but it is keeping you hooked into a marriage where you service his depression in a way that probably enables it. I guess I'm saying I think you're probably a crutch to him too - like the alcohol. You can't take away the bottle but you can take away the pacifying services he's extracting from you.
Do you have new year's resolutions?
I have two: to see my friends more often (I have been really sucked into my work this winter) and have people over to the house more often. Which is strange now H is living in it again, and awkward, but I won't be isolated. The second is to have dinner at the table with my kids every night. I've been letting them eat in front of their screens, or in their bedrooms - partly as an easy life for myself - but it's led to some shocking table manners and a bit of disconnection. I don't like that laziness in me. So no more of it.