Murder Or Relieving Someone Of Suffering: Where Do We Draw The Line?

Euthanasia is the practice of intentionally ending a life in order to relieve pain and suffering.
There are different euthanasia laws in each country. The British House of Lords Select Committee on Medical Ethics defines euthanasia as "a deliberate intervention undertaken with the express intention of ending a life, to relieve intractable suffering". In the Netherlands, euthanasia is understood as "termination of life by a doctor at the request of a patient".
Euthanasia is categorized in different ways, which include voluntary, non-voluntary, or involuntary. Assisted-suicide is legal in several jurisdictions, including Belgium, Luxembourg, the Netherlands, Switzerland and four American states (Oregon, Washington, Vermont and Montana).Non-voluntary euthanasia is illegal in all countries. Involuntary euthanasia is usually considered murder.
So hopefully we all know who Jack Kevorkian is, "Dr. Death" is pretty famous I'd say. His work is the very reason I wonder where we draw the line of murder, and the right to die. Rebecca Badger, a patient of Kevorkian's and a mentally troubled drug abuser, had been mistakenly diagnosed with multiple sclerosis. The report also stated that Janet Adkins, Kevorkian's first patient, had been chosen without Kevorkian ever speaking to her, only with her husband, and that when Kevorkian first met Adkins two days before her assisted suicide he "made no real effort to discover whether Ms. Adkins wished to end her life," as the Michigan Court of Appeals put it in a 1995 ruling upholding an order against Kevorkian's activity.According to The Economist: "Studies of those who sought out Dr. Kevorkian, however, suggest that though many had a worsening illness ... it was not usually terminal. Autopsies showed five people had no disease at all. ... Little over a third were in pain. Some presumably suffered from no more than hypochondria or depression."
"What difference does it make if someone is terminal? We are all terminal." Jack claimed. Well yes I suppose, but why exactly do we need help committing suicide? I'm more than sure that people are capable of committing suicide on their own. For instance, Oregon requires a physician to prescribe medication but it must be self-administered. What happens when your patient can barely remember how to hold a spoon let alone remember what the hell you said five minutes ago? Even if they do consent, what if they don't remember it?? I just have this feeling that there are too many variables to somehow make this okay