People should have an option....
As to whether they want to continue on with life. Even if they are completely "physically" healthy. There should be clinics set up where you can go, fill out some consent forms, talk to a psychologist on staff, than wait a certain amount of time, and if you still feel how you do, you should be able to go back and get a painless shot and that is that.
Suicide is not shameful if you have no one OR if you know one day you will absolutely be totally and completely alone. How torturing would an existence like that be? I'm almost there myself, and in a few years time I almost certainly will be. What would be the point in continuing on?
It has nothing to do with depression. Everyone who reads this is going to be dead one day anyway, one way or another.