If you want to seek professional help, you should seek is your school counsellor. Whether your friend needs help or not, the school counsellor can advise you on what to do next. If a school counsellor is not available, another option is your GP . GPs are trained professionals and often deal with situations like this. Many doctors will bulk bill, meaning that the consultation is free.
Psychologists are another good option to consider.
These are either free, or the cost of a local phone call.