When mistrust is at mist, mistrust comes to be! To mistrust is not only a test to the mistrusted but also to mistrust is a test to he that mistrusts. To mistrust is not only lack of confidence of the mistrusted but also to mistrust is lack of confidence in he that mistrusts.
Now, lack of confidence in oneself is lack of knowledge of oneself and because of the lack of knowledge of oneself thus one is not complete or one lacks true form and because of that very lack of true form thus one mistrusts, but one mistrusts because one truly depends on another to complete what one cannot.
Interestingly, if one were complete, one would never mistrust because one would never depend on some other because for one being complete, one will renew in abundance and nothing would ever be lacking, not even lack for lacking!