You don't have to trust anybody, but sometimes you have to trust someone.It is not advisable to disclose your pass phrase or your bitcoin portfolio to everyone, because doing that can endanger your bitcoin investment, but for the sake of any unforseen occurrence, it is advisable you let  someone know about your bitcoin investment by so doing your bitcoin investment will not be lost. So, while investing in bitcoin do not hide your asset from everyone but have one or two persons that would know about it.