Does it refer to 1 or 2? I think it's 1 considering the whole context. They wouldn't say the original sentence in terms of conditionals, I guess. 1 also seems not a perfect conditional structure, but it can be possible as a non-conditional clause and a conditional one can be combined. What do you think?
1. As I felt so lonely, I might have lost all hope.
2. If I had felt so lonely, I might have lost all hope.
pp97)There was a time in my life when I was feeling very lonely. I didn't think I had any friends. Every day I came home to an empty house with an empty heart. Feeling so lonely, I might have lost all hope. But my dog, Fluffy, was always at the door waiting for me. ...Those bad times passed eventually, but they would have been a lot more difficult if it had not been for my faithful companion, Fluffy.
There's no 'if' about it. S/he felt lonely.