How much information to withhold from your other half? If any at all?

People say that there should not be any secrets between a couple, after all, a relationship is all about trust ain it? So is there a need to adopt a "Tell everything" principle, or is it more of a selective "Tell everything" way of principle?

That has left me grappling within myself as there have been times that I withheld what I really want to do or say, simply because I want the best for my other half. Always seeking to have her best interest at heart, but from MY perspective. Big question is, what is it that she really want? Why is it that she does not get the opportunity to put her best foot forward and put your interest before hers? So when you think about it, what is it that she really wants? To do what you want to do, or is it to do what she really is interested in doing? After all, the irony is that, what she really wants to do after considering other factors, is really, what you want to do!

After much pondering, we have decided that the best way is really, to tell the truth. To tell each other how you really feel, and how much you really want to do each event. Subsequently, then we decide upon which activity would give us the best satisfaction. I know this sounds a bit like a logical way of doing things, but at this present moment, this appears to be the best option that would make both parties happier. How would you do it?

"Love is that condition in which the happiness of another person is essential to your own." ~Robert A. Heinlein~