As a rule, having boyfriends /girlfriends is something that is not allowed in Islam. Here are some things to think about:
• Marriage provides a legal document (marriage certificate) and witnesses, which provides protection for women. Can you imagine working for an employer without having any contract, basing all salaries purely “on trust”? Maybe some employers will be honest and will give regular salaries with no contract at all but can you afford to take that risk? Likewise, how can a woman live with another man and have children with him without being married? Maybe he will be honest and take good care of her but can she take that risk?
• Having such relationships outside marriage is not legally binding and there may not be any witnesses, increasing the chances of a living in abusive relationships
• Not having any marriage contract or witnesses might make such couples question each others’ level of commitment to maintaining the relationship
• Many people have relationships outside marriage but you will find many women suffer and end up as single parents. This is so common that many governments such as in the UK provide benefits for such women
• Being a single parent can be extremely difficult, not only for the parent but for the children especially if they have no idea who their father is and perhaps only ever hear negative comments about him. Children do not have parents then who can be good role models for how they should live their lives and manage relationships well
• In many cultures (not just in Muslim societies) marriage is very important and honourable and even when people have pre marital relations there is an ultimate aim of getting married
• It is common for people to have more than one boyfriend /girlfriend throughout their lives. This can increase the amount of stress and psychological problems associated with breaking a relationship especially if others did not know about the relationship and cannot support them at such a difficult time in their lives
• When people easily have many boyfriends /girlfriends without always knowing each other well, there is a possibility that they are more likely to get diseases such as AIDS
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Mahir Gazdar's Writings 
I am not aware of any religion that allows sex outside the sacred bond of marriage.
I personally believe the fear of AIDS to be a very poor argument in favour of chastity. People tend to forget that you only need one sexual intercourse to get contaminated. And also using condoms protects you – from AIDS and from pregnancy; but does that make sex outside marriage more acceptable?
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Thank you for the comments. I agree with your points here. However, apart from the basic Islamic principles here, I was not referring to any particular religious text but to what many people in society are doing…
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