No, the correct answer for most of the people you listed is "it's none of your business." Your wife, or partner, deserve all the answers you have, with the exception of the forward looking ones. No one knows the future with certainty. A medical doctor, the medical related questions. Everyone else? It really isn't their concern.
This is my primary problem with the way trans people are treated - we aren't accorded basic human dignity. When I tell people I'm trans, I am asked questions they'd likely never DARE ask another person. Why do they ask me? It's really simple - I'm not a person to them. It's obvious - you can read it in their body language. It is NONE of my friend's or coworkers business who I sleep with, or what we do when we are together. (I get graphic questions about both of those things.) I don't owe anyone prognostications about my future. People have no right to ask me "do you think you'll regret it and switch back?"
I'm asked these things, and objectified as a collection of body parts and medical procedures, because most people simply don't see me as a fellow human being. There are exceptions, but for the most part my experience has been that as soon as I reveal that I'm trans, I cross over from being seen as a woman, to being seen as some sort of a thing - a guy who's done such bizarre things that he's no longer recognizable as a person, but is rather a thing.
People don't need to psychoanalyze me, to figure out which kind of a "thing" I am. They need to treat me as they would any other human being, and take me at my word that I am who I say I am. My motivations for doing whatever it is I've done are none of their business. I might share those things with some people, and not others, at my discretion.
I'm very sorry to see these same attitudes persist here, but they are prevalent in society as a whole, so it shouldn't surprise me.
What people do need to know about someone like me is perhaps that I have lived every day of my life in fear. For the first 50 years, it was fear of discovery, rejection, ostracism, and physical violence should it be discovered who I really was. Now that I am open about who I am, I experience all of those things - rejection and ostracism, and I know that physical violence may await me at any time, simply because of who I am.