Hi Stu,
I am new to this myself but I'll give it a shot...
Have you read DB or DR yet? I recommend DR. If you have, then you know you need to start detaching emotionally from the situation, for your own sake. I know it feels like the opposite of what you want to do, but it is what you need to do. I hear your fears about her thinking she is happier without you. I have the same fears, but my H is in the same house in another bedroom. He seems to content to stay there and it hurts so much. Most of us here in similar situations struggle with wondering how long we can hang in there and wait. I am struggling with that too. That is why GALing is so important! We have to be able to find ways to survive the emotional pain, find some enjoyment in life, and the other benefit is that is more likely to make us more attractive to our WAS again.
I wish you all the best... get those books if you haven't already!
Rocked