Is breaking up in a relationship a crime?

I have a doubt. If a couple go around together for 2 or 3 yrs and then if one of them decides to break up the relationship,then will the other member have any grounds for claimin damages.the couple would not be having any physical relationship and no kind of monetary exchange would have taken place.what would be the consequences if the couple had physical relationship and then one of them breaks up relationship? I m facing this situation. Also i wanted to know if one has phone sex,will it be an offence?please guide me wit your valuable suggestions.