Trust is built on openness and not half truths. There are instances you try to protect yourself and keep the important things to yourself alone especially when it comes to your life because you wouldn’t want to share all details to someone unless you’ve accomplished it. But when it comes to some certain contexts, being open completely is important to avoid trouble.
For people you believe you’re trying to protect yourself from
I don’t think telling them anything in the first place is required
But if one is to open up to someone
I believe they should do that
But there are people you don’t trust
And I think nothing telling them things is better inside of half truth they they can use against you in the future
But when it comes to relationship
I believe full truth is better because when half truth starts and the trust is lost, it’s very hard to get back on track