Everyone who is against euthanasia is doing so based on their religion. Pushing their beliefs onto another person. Euthanasia may not be the choice a patient would make, and it may not even be one that a patient would consider, however it should at least be an option they have. Those who are against euthanasia have every right to suffer through their disease, but just because your religion says it is wrong doesn't make it wrong to others.
Similar to abortion, I think every human has the right to decide on their own life.