Once I realized I needed to do something in the way of transition, I knew I needed to do it. I will compromise for my wife, if need be, on the degree or timing of my transition, but I knew that no transition was not an option. Before I came out to her, I knew that she might leave me, and I was prepared to accept that as a consequence. It made coming out a scary proposition, but knowing that I had to do it was what got me through the fear. So far, it looks good for her to stay with me. Yay!
As for the rest of the family, my parents have died, so I just have two brothers. One was safe to come out to. The other isn't. We are not a close family, and he is 3000 km away. I'll probably never see him again anyway, so I have no reason to come out to him. We exchange birthday and Christmas emails, and I'll continue to sign these with my boy name for now. He may find out eventually. (At some point my email will probably get changed to "Kathy", so that will let the cat out of the bag.)
He'll either be cool with it or he won't, his choice. It sounds harsh to say it, but it will be no great loss to cut him out of my life if he is hostile. What is two less emails a year?
I have some cousins. Two, I am not in contact with, so no issue there. The third is a birthday and Christmas cousin, like my brother. I'll handle him the same way as my brother.