Assisted suicide is to deliberately help or encourage someone to end their life. (Euthanasia is the act of deliberately ending someone’s life to relieve their suffering).
Palliative care is aimed at supporting people at the end of their life. This may include for example, withholding or withdrawing futile treatment, which is not considered to be euthanasia or assisted suicide. Lawful care of terminally ill patients, such as withholding or withdrawing futile treatment, never involves an intention to end a patient’s life.
Nurses working in palliative care are sometimes asked to help end someone’s life: 'I can’t go on like this, can you give me something to end it all?' Patient assisted suicide has been described as 'the provision of drugs and/or advice so that a patient could take his or her own life'.  This is illegal in Australia. 
It is important to acknowledge that some patients are expressing a desire to die rather than requesting direct action. These requests to die can be made when someone is depressed or emotionally distressed. For example they may feel that they are a burden, or perhaps are suffering intolerable physical or emotional symptoms. At other times decisions have been made carefully, such as deciding that life is intolerable.
One study of terminally ill patients in Canada  found that the desire for death was transitory (dependent upon symptoms at the time). This indicated that potentially treatable symptoms could in fact, drive people to suicide. Further research, on who is choosing an assisted death and why, is needed. 
If someone is talking about taking their own life, whether or not they are asking for help to do it, this situation needs to be addressed urgently. Actively listening to their concerns and fears can help ascertain why they have come to make this request. Talking to others within the health care team whenever possible provides a multidisciplinary approach to a situation that shouldn’t rest with one practitioner.