Hello friend,

It is a very good question you have asked. Most of HR people would go through such dilemma.

HR person needs to strike a balance - on one hand he is required to provide support to employees, help them within company policies and rules. Provide forums for motivation and coming together - yet keep a distance which every employee should feel and be aware of.
HR is required to keep a lot of personal information about employees - confidentiality is a must. Any friendship which is beyond a certail limit is likely to cause stress as you may either unknowingly or knowingly disclose information to others.

HR also requires to take firm stands on administrative issues - for example if you are very friendly with some employees and you want to issue them disciplinary memo for late coming - such situations will put you in to dilemma. Therefore it is better to be friendly but not VERY CLOSE. You should be able to create an image that everything legitimate will be done - it will be done impartially to all - no special treatment will be given to anyone simply because he/she is close friend. Such image will be essential for you to function as a professional HR officer.

Hope this helps.

Regards,
Kenita