Hmm, I understand that many people are ego driven. Their only concern is to get what they want and they view others as objects, instead of sentient beings. You find that people change their colors all of a sudden, because it is hard to pretend for too long.
People usually put their best foot forward, to try to impress the other person into liking them and thinking that they are a good person. Then if they do not get the result that they want from the other person, fustration sets begins. This fustration will be displayed in the relatinoship.
If a person truly likes and care about the other person, then, they will want the other person to be happy. When they cannot get what they wnt from the other person, they will not get fustrated, instead they will respect the choices of the other person and care about them just the same.
People seem cold sometimes because they are afraid to open themselves to getting hurt. History is not a very pleasant thing to read on this planet. People are careful about being a victim.
All in all, I would consider who are the people that you are speaking about. What culture are they from? What is their personal back story? I tell my friends that if you want to find nice people, the best place to seek them out is in a church, temple, or other house of worship. Most people believe that the creator is a loving being, one that rewards good deeds and punishes bad deeds. in all honesty, they are most likely to try to walk the path of kindness, than other people who are driven by their own personal agenda.
I hope this helps you. Best wishes.