Euthanasia: Should it be legal or illegal

Euthanasia is the painless killing of a patient who suffers from an incurable disease or is in an immense amount of pain.  This topic is very controversial amongst people of all states and people tend to have very strong opinions regarding euthanasia.  While I understand both sides to this argument, I believe that euthanasia should be legal in all states.  After all, it is the patient suffering and they should have the choice over their life.  Nobody else understands the pain or suffering that they are going through and ultimately it should be their decision in the long run.  

I am curious to hear what you all think of euthanasia.  Is it immoral? Also, if someone is unconscious for years (i.e. in a coma where they are never going to wake up), is it okay for a family member to give them euthanasia?  I am interested to hear all of your thoughts.