According to Wikipedia, suicide is the act of a human being intentionally causing his or her own death.
I firmly believe that nobody has the right to take away his own life no matter what the reason they may have. God has given each of us life, and we are all responsible to take care of it. In fact, this life is only borrowed and He is the only one who can take it back when He wants to, and when it’s our “time”.
On the other hand, Euthanasia is far different from Suicide. According to Wikipedia, Euthanasia refers to the practice of ending a life in a manner which relieves pain and suffering.
Euthanasia is when you (and other people affected) can no longer bear someone’s pain and the only way that can free him from it is by ending his life. For some cases, when the subject person can still be able to express himself, he himself may request that, should his situation worsen, people around him (family/doctors) will not have to try to revive him. But usually, there are more cases when the patient’s life only depends on a machine, his family can already decide on euthanasia.
In short, for me, Euthanasia is more acceptable than Suicide.
Suicide is just a choice some people make thinking they can escape from reality, while Euthanasia is a choice people make to end somebody’s pain.