Moosey, your post is brilliant! That's exactly what it's like. And such a lonely feeling. Who do you say, "I'm feeling overwhelmed and resentful and I'm just finding this kid really annoying" to? Your social worker? Friends? Your dp? All of whom will always remember that you said this.
Nah, you come onto MN and share it with us battle-scarred gob-crackers who know there is never a fairytale ending. There is hard work, struggle, overwhelming emotions, emotional numbness, putting one foot in front of the other, then gradually shafts of light start coming through the lights, little twinkly nuggets of joy and eventually love. Those nuggets never take up the whole sky - there's always clouds - but usually you get enough of them to light your way and make it all worthwhile.
I felt hopelessly lost at the start. All I can remember were these intense feelings of self-pity and being completely overwhelmed. I'm ashamed to acknowledge how much I was wrapped up in my own feelings and how little empathy I had with dd. I've said before on here how shocked I was to look back of photos of her at that time. I was blithely telling everyone that she had settled in beautifully, but every picture I have of her shows this sad, anxious little face with big wondering eyes. Indeed, on her first morning with us I was thrilled that she slept late, so I got some much-needed alone time. Eventually I went and looked in her room and she was just sitting up, staring around this strange room. Lord knows how long she had been like that. I feel sick when I think about it now - why on earth did I assume she would call out for me?
The one thing I am glad about is that I am a very tactile person and she was very clingy, so I carried or wore her everywhere. I know how rare and precious physical space can be, but my advice would be at least to provide lots of physical contact. It doesn't substitute for emotional connection, but I think it bridges to it and helps it come faster. And on the way provides a great deal of comfort.