Please Help. How do you make a suicidal person realize it is the ultimate act of selfishness?

If someone is hell bent on suicide then you cant do much about it.....they need professional help.. What you need to do is safe guard yourself against being sucked into this mire . You can turn your world upside down trying to help and all to no avail...Know when to leave alone and to get proper help...this person really needs some good councelling.