I think suicide should be legal. After all, you can't really force a person to want to live... If you do, they'll only feel even worse. (Believe me, I've been there... (and no, I'm not emo.))
I mean, of course it's terrible when a person commits suicide or even just tries to do it and fails. It's horrible.
But as I said, if you force a person to live against their explicit wish, they will get worse.
And... think about it. If someone suffers from a incurable illness, would you rather have them die a painless death or die a horrible, painful death?