Trust

I remember I was in high school and we had a Physics exam. Few days before the exam I lost my Physics book and at that time it was not easy to find another copy as each of students would receive their school books at the beginning of the year and that was it; no easy source to access to another copy. I took that exam anyway.
Some days after the exam one of my at the time close friends gave me a copy telling me she did not know her older brother's book was still in their storage, some pages in the book were missing and it looked quite shabby. I got happy until I saw something in the middle page of the book where I had written my own name on top of the page and that was when I realized the book was, in fact,my own book. I was shocked and sad and I asked myself why she actually did that but never asked her the same question. I finished the high school while we were still friends. We separated since we went to different universities and then I just stopped talking to her.
The fact is that I trust easily and I repeated the not telling part with a very few others; question marks lightening in my head and never asked them or better to say never dared to ask them and the relationships are or were not THE relationships.
I know many would say it's better to say and untold stories are what build higher wall between the two sides and I agree with this pretty statement in general but perhaps sometimes that wall is necessary to protect us from receiving not very pretty deliveries from another side. I think when we trust someone and are trustworthy according to that someone, it's easy to hear and to be heard but it's way too difficult to fix a broken trust or build a relationship on trust and let's leave "hearing and being heard meanwhile" alone in some of these cases. I'm not sure if there is any equation that could work out the setback in reality but I'm sure words are not "always" helpful.