Relationships

Popular wisdom on relationships says that men change or turn away after sex. I believe this notion stems from grandma’s wisdom that men are only after one thing( the much maligned men). Is this really a fact? I’m not a psychologist, nor have I done any kind of research on the topic, this is a notion prevalent in India and I believe elsewhere too.
The popular idea that the girl is too easy or the girl is too cold or frigid? Does it all stem from the fact that both the sexes are just seeking self centered goals or self gratification in a relationship, though they claim to be in a relationship which is all about caring and sharing? I’m not offering a critique on society or men or women for that matter, I’m just trying to figure out the dynamics in this case? Is it really about fitting men or women into certain prototypes or  is there more to it? Are people genuinely trying to figure out what is the cause of a person’s behavior in a certain manner or situation?
I once knew a person who told me that men like you more after sex because they feel accepted. Her statement I’m sure came from her experience as she had been married for many years. How far is this true? Very few married women actually make this kind of a statement, so do people just repeat what the other person has said or they try to analyze things?
I would love to hear what your take on this is.Please feel free to leave your comments. It's okay to leave your comments anonymously if you are not comfortable disclosing your identity.