Peony - my heart too goes out to you.
I suffered PND after my son was born, but seeked some counselling after about 8 months as I felt I just felt so desperate for help. I personally wanted to try that route before getting antidepressants. I have alot of 2nd hand experience of antidepressants - friends and family members - and they too have described feelings of numbness. I think one of their effects is to stabilise your moods - so they don't allow you to get too down, but also seem to prevent you going too 'up' aswell. Please don't think I am negating how necessary and helpful they can be - I certainly wouldn't have turned them down had my counselling not helped so much.
So, ultimately this is a hopeful message. I found the most amazing therapist/ counsellor who has helped me to become a much happier person. I have now been seeing her for a year (maybe more?) and we have worked through so much stuff. I think with all cases of PND there tends to be another issue that motherhood is bringing into the foreground for you, whether you are aware of it or not. So, although I still have bad days/ weeks - on the whole I feel so much happier about myself, about my son, about my relationship with my partner and most of all about being a mother.
One thing I would say is though - it is soooooo important to find someone who you work well with. Before I found the lady I see now, I went to a chartity in London which deals with parenting and children from a very 'Freudian' perspective, which I found really didn't work for me. So, I sought help elsewhere - I personally decided to go privately - vey expensive (£30 per week), but I considered that a valuable thing for me and my family and thus worth it (Plus she would have offered concessions if I couldn't afford it). If you do decide to look elsewhere for someone to work with - I can recommend some helplines/ organisations who would put you in touch with someone in your area who is experienced with PND and issues around motherhood.
Last but not least, sorry if I am going on a bit, don't forget that motherhood is a bloody hard thing to adjust to - it changes your life completely, and it is a very very normal thing to find it difficult to come to terms with. It is not easy - any mum will tell you that - and some people (for whatever reason - but certainly not through any defect in themselves) find it harder than others for a while. Everyone lives in different circumstances.
I really do think you have been very brave to try to talk about it with someone. I felt quite brave myself when I started. Counselling is not an easy road - sometimes you have to take one or two steps backwards to take a leap forwards - but I really have found it has changed things around for me (and thus my whole family).
Have I rambled too much? Sorry.