This sounds so difficult for you. As a Christian, what you are going through resonates with me, as a similar thing has happened a couple of times to me. The first time, I remember being bewildered and very, very depressed. It just felt like there was nothing there. I went to church, went through the motions, prayed. Everything - but nothing. It felt like a literal brick wall.
It was one of the most difficult experiences I'd been through, as my faith had always been so deep, and for me had been incredibly experiential and emotional. So I decided to go with it, and almost as a cerebral exercise to see whether my faith could survive through a more rational way of looking at things. I studied theology at a secular uni, and if anything would turn me away, that would
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But instead I found, as greenheart referred to, that this was a much documented human condition, and something that happened over and over, often referred to as 'the dark night of the soul' or 'a desert experience.' It certainly felt that way to me. I couldn't see a way back. But studying turned it round for me - I found a rationally robust basis for my faith, and found that it could be more than an experiential thing. I realise this doesn't work this way for everyone, but this was my experience.
I asked myself if I could still believe these things when exempt from any kind of feeling or sense of the presence of God. And for me, I came to see that I could. Of course, without the emotion and the experience it is incredibly difficult, and I have times like this occasionally, where I remind myself that for me, my faith is founded on a rock of reason and evidence that I have studied and accepted, and at times this has had to be enough.
At those times, it can be good to take a step back from all the 'trappings' - prayer, worship etc etc, and almost embrace the desert experience to see where it goes. I can only say this having come out of it the other side, I know that it is not that easy - but for me it led, both major times, to a deepening of faith that changed me profoundly.
I hope you can come to some peace with where you are, and have a glimmer of hope as to how things could be. I'm very happy to talk more via pm if you would like, as I remember the cold feeling surrounding me. Thinking of you 