I watched my sister die from ovarian cancer and would not wish it upon my worst enemy. Yes she was connected to a syringe driver but she was still in pain. We knew there was no hop or cure for her and prayed that she would be taken quickly. This was not for our benefit but for hers. I believe in persons having a right to die with dignity and provided they have the mental capacity to make the decision it should be a right.
As for the poster who said that sick animals should not be put down I'm glad he/she does not look after any animal belonging to me. I am an animal lover and would not want to see any animal suffer needles pain. I had my last dog put down because he had no quality of life any more and even though it almost killed my wife and I we are both glad we made the decision.
Love many, trust few, always paddle your own canoe