Yes sometimes it takes a while to open the book of the human heart of another. This is the workings of karma we have with them. Yet eventually a humans true colors manifest. I found this thread very wonderful and extremely insightful. I have met such people who could cast their 'lantern light' on another and I aspire towards being the same.
"What gives one insight into another is, in the first place, his sympathy. The seer first develops the quality of love. He whose heart is kindled with the love of God is capable of the love of humanity. The heart thus kindled with love becomes a lighted lantern, which throws its light on every person the seer meets, and, as this light falls upon the person he meets, all things about that person, his body, heart and soul, become clear to him. Love is a torch that illuminates all that comes within its light, but it is the knowledge of God which is the key which opens the hearts of men." -- Hidayat Inayat-Khan