Chinchilla,
So sorry to hear that things are really grotty right now, You brought me to mumsnet (saw your postings i think on Raising Kids), and you have made me smile lots in the last few months. as SAHMs we share a lot of experiences.
I just thought I'd chip in with some experience of my own. About a year after DS was born our relationship became really difficult, largely because dh lost his mum, had to make a career change (which made him feel he'd failed) and he became depressed.
Whilst I have EVERY sympathy with you for your PND, please remember that your dh is having a hard time of it too. Sometimes, as the partner to a depressed person you don't know what to do for the best, whether to offer help, or keep out of the way. Sometimes that seems to be the easiest option, just to avoid bringing on a row, even tho' your depressed partner is seething cos you're not trying to help.
We went thru months of hell, and he nearly left twice (I came close on a couple of occasions too, but gritted my teeth - I couldn't bear the idea of living with my mum, which would have been my only alternative). I went to the doctor before he did, just to get some advice on how to live with him in this state.
Since he got his Prozac things have improved, tho' we still have days which are very hard. What I suppose I am saying is that if he is trying to help, as in your last posting, please tell him you appreciate it, and please try to understand that your depression is very difficult for him too. I'm not defending if he is really unhelpful, just trying to point out that he may not know how to help.
I'm not a great beleiver in counselling (too much like washing dirty linen in public for me), but perhaps you and dh could visit your gp together to discuss how you are??