It is not healthy i think. Each of us can have their private life but if it is something that should be called "a secret" it's better to not hide it.
No. It's too exhausting and more harmful than rewarding.
no, it's not healthy to hide things or lie
I don't know about "secrets" per se, but one doesn't need to share EVERYthing.
yes,as long as it does not hurt them
No, unless it's like a surprise birthday gift :P
Yes..if they aren't grave or the time is not right..but hiding it forever without a good reason is not fair
No. It will bite you in the ass in the long run.
Absolutely not, what can you be doing that's so bad that you need to keep it from telling Your individual. And always remember that it eventually will come to the light and when it does its going to blow bigger then what it was just because you wanted to be sneaky about the situation. *communication is key*