I used to ask myself that. Am I unhappy because I don't fit my idea of how I should look when presenting as female? Is the source of my jealousy towards other women the fact that I learn to be in bed with them rather than be like them?
But then I remember having that desire to be a girl from a young age and the accompanying disappointment when I saw my reflection. I remember that strong desire to be feminine at other times, and only pushing those feelings out because guys were ridiculed for being feminine (not just by their peers either). I remember at one point I preferred hanging around with girls, which changed because (again) it's "not what boys do". I remember the struggles I went through when I first tried to socialise with boys. I don't have those struggles nowadays and tend to get on with most people, but those early signs seem to say something.
And now, I remember how content I feel when I present as female and how much that shows in my photos.
*shrug*