Some of our biggest interpersonal problems could be solved if we could just take the time to understand each other. I once heard that if we could know the entire story of somebody's life, we would never have any reason to judge that person, and we would just love them.
1 Samuel 16:7 says: "The Lord seeth not as man seeth; for man looketh on the outward appearance, but the Lord looketh on the heart"
Because God knows everyone perfectly, he can love everyone perfectly. As human beings, we don't know even our closest friends or family members perfectly. Sometimes this is because we don't open up what is lodged deep in our hearts to other people, and other times it is because we don't take the time to listen and find the things in the hearts of those around us. In other words, we look on the outward appearance.
I hope Katie(my sister) doesn't mind if I share this, but when I was home I went to the mall with Katie. She was walking in front of me instead of beside me, and she probably didn't even notice, but for some reason, I was bothered. I started to get frustrated with her, and then I realized that all I needed to do was to ask her to walk next to me. I did, and instantly she walked next to me and the problem was solved and I was happy.
Sometimes all it takes is realizing that we are expecting people to read our minds, and we haven't even communicated our needs and desires to them.
Other times it is because we haven't taken the time to get to know the persons heart. If we were able to look on the heart as the Lord does, we would understand the things we perceive as negative behaviors of those around us.
I realize that we will never be able to truly see the hearts of those around us in this life, but that is when we pray for charity. The Lord can see for us. He will grant us the perfect love that that person deserves and most often so desperately needs.