I think hiding it from your wife is a terrible decision. Unless you did it absolutely alone, wore lifts to your desired height before getting to know everyone in your current social circle, and didn't tell or see absolutely no one in your family in recent times, your LL secret will probably come out someday, in some form. It's better to not risk something like that.
You shouldn't be married to a person who doesn't understand you to the point that they can't accept you were in so much pain about your height, you went through something as drastic as this, anyway. I stand by my point in other threads that physical attraction and looks are totally biological in nature. You don't need to worry about being rejected for telling your wife, of all people, that you went through LL in the past. Most people's minds wouldn't even be able to really picture you were shorter once. But like everything in life, everyone has to make their own decisions. I think the sooner you can tell a serious partner, the better.
To answer the thread:
Do you plan to keep this secret from everyone except parents or siblings?
No. I'd just avoid telling it to people I don't know very well, since there's no reason to, and they would never understand it. It's not even possible to hide something like this when you just return taller than you were in your adulthood, anyway. It's a personal decision and I would be fine with the ones who are close to me knowing. Ideally, I'd like to believe the people I choose to keep close to me in my life would be understanding enough to the point of being empathetic if I ever went through something as radical as LL just to deal with my own psychological pain.
What about girlfriends or future wife?
I'd tell them as soon as I felt it is appropriate, if it is a serious relationship. They have the right to make an informed decision about their future, and I would also like to judge their reaction. It'd also be personally hard for me to keep living and thinking I'm deceiving someone, even though I understand everyone here who chooses not to tell; everyone wants to be judged/loved for who they are, not their height.
What about your kids height? Wont you worry? If they are short, how will you explain it?
Every single member of this forum who's going to have children someday is going to be very conscious about making sure their sons reach their maximum potential height, with HGH treatment, great nutrition, etc. But if I ended up marrying a very short woman, I'd do IVF to not risk having sons.