In Islam, sex is the consummation of Marriage. The reason it is Haram (prohibited) outside Marriage.
Sex is more than just two physical bodies coming together for pleasure and for this reason one should only engage in the act with their husband or wife and not boyfriend or girlfriend.
The reason why some people cannot forget about their Ex many years after they have broken up or some people kill themselves after a relationship has come to an unexpected end is as a result of their souls they have tied with the wrong people through sex.
Anytime two people engage in sex, it does not just involve two physical bodies but instead souls and spirits are involved and also they release a huge part of themselves into each other as a result forming an emotional bond with each other whether they like it or not.
The more they engage in sex, the more the bond is strengthened making it very difficult to break. When the relationship comes to an unexpected end, the individuals therefore find it very difficult to forget about each other and that is the reason why some conclude they can’t live without each other and some also still cheat with their Exes even when in a new relationship.
They have tied their souls with the wrong people.
One reason why only married people have the right to sex, is because at the altar, they vow till death part them; meaning there is an assurance they are going to be together forever. Breakups and divorces are more painful than death because of the deep emotional bond formed through sex.
Sex should only be engaged in after marriage. @Ivon Hanson.
Ignorance is difference