It would seem that he is hungering for something. Many guys who do this eventually come across a woman who is very interesting, so this can be very dangerous. It is when you can comfortably share private sensitive topics with your partner and trust that he or she will not take advantage of you with this information. It is about trust, openness, and developing a soul mate that knows you inside and out and loves you anyway. Love does not turn into an obsession but lust or insecurity or possessiveness can become an obsession.
Obsession is about anxiety and worry and is really a mark of immaturity.
Something basic in society changed. The only time not wanting sex was a cultural ideal was 100 years ago in the Victorian age. Every other age has promoted the value of sexual interest and desire, although it varies from culture to culture. Sex wasn't talked about until the 1960's until the revolution of the birth control pill. It changed sex in our culture forever and liberated women that they could have sex without the risk of getting pregnant.