Relationships

I know very little about the relationships between men and women.  I know about sex, but it isn't the same.  I am trying to learn, but I am lost and have no idea where to go to understand.  When I was very yong, I thought you just had to give love in order to get love back.  What a fairy tale that is.  It seems to be mostly about manipulation that occurs between the two people involved.........relationship politics.  It is a complex thing and I am too simple to grasp it concepts, much less exercise them.   It seems so easy for most people.  Why is it such a disaster for me?