Orm, you sound lovely. I have just read this entire thread, and my heart has gone out to you more than once.
Firstly, with my MH Nurse hat on, I'm going to take a leap and say that your depression, whilst very real, is actually very likely caused by your husband. He has used your depression possibly as an excuse to behave cruelly. He wanted you to go to the doctors and get 'fixed'. But whilst citalopram (and you're on a fairly low doseage by the way) does blur the edges, it papers over the cracks. You will not heal until you address why you need the ADs in the first place. There are two types of depression, some of us have a shortage of the 'happy' stuff in our brains, so ADs boost the levels up to normal; others simply have a hell of a lot of shit to deal with, and living with a man-boy, who everyone thinks is kind and wonderful, but actually treats you with disdain is enough to have the happiest of us reaching for the citalopram.
My husband made me feel like shit. Everyone thought he was kind, sensitive and lovely. He put me down, criticised me, undermined me, ignored me, mocked me and made me believe that I was totally unworthy. I too took citalopram. It made me tired, and a little numb, it made me introverted and cut off from reality. He moaned about having a depressive wife, with no get up and go. Once I'd told him to get up and go, I got better, and the meds were no longer required.
I won't judge you at all. Only you and your husband know whether you have something strong and solid enough to build a future on. My ex was having an affair, but he had denied this for months and months. I actually threw him out, not because I found out for sure about the affair, but because he was slowly destroying me - my confidence, my sense of worth. I had 4 kids to bring up, and he had knocked all the stuffing out of me. I threw him out, filed for divorce, lent on the wonderful people on MN, and picked up the pieces.
I think you need space from your husband. Even on a temporary basis. He needs to see what he has done, and do absolutely everything in his power to repair the damage. He needs to see what he stands to lose. He hasn't done nearly enough. He denied, he didn't accept responsibility, and when I read the bit about him asking your friend how honest he should be, a huge alarm bell went off - he doesn't get it. He will never get what he has done, because he detached from you long ago. The bit about him being on holiday 'but not being there' really resonated with me - we had a final holiday like that. My husband told me over a year before I threw him out that he longer loved me. I knew then, though I went through the motions of trying to become what he wanted, that we were dead in the water. Nothing would ever undo that pain and rejection.
You have little self-esteem, because you have mirrored your sense of self on what he done. It has eaten away at you. If you want him, really want him, then it has to be on your terms, and he has a hell of a lot of work to do to win you back.
Dig deep, find your courage, and decide what you really want. And if that takes time, then take as much as you need. And don't protect him by not leaning on people in RL. You need support and your family. He's in the wrong here - not you. You are worth so, so much more love.