Hmm, well I am in the same situation myself. Except I am the boyfriend. Well its a lot of questions that I can''t even answer, but here it goes. Most true transgendered people are not gay, nor do they care about it, I mean some are willing to try it after a surgery and see what it is like. Research was done a few years back, and they actully discovered that transgendered people had the same brain as the desired sex. The brain between a male and female have many different characteristics, and that was how they drew the conclusion. It is the actual chemical eqautions in the brain that determine this, and how the brain reacts to it.
I love my Girl Friend very much, and I want to marry her, but I just don't feel right about living the rest of my life like this. I heard some people say it is worst than being extreamly over weight. Its like you are in a prison. And most people have noticed something was wrong with them at a very young age.
Its a terrible situation to be in. However the fact remains that we still love each other in sickness, and in health. I really don't know how to put it, its very hard to explain,but hopefully you will work it out.