I don't really have ethical or moral beliefs in suicide itself. What i believe about suicide is just conclusions based on how I understand the universe, and my motives.
First of all, I believe that beliefs are the foundation of thought and knowledge. They are the only method we have to make decisions and think. True we have what you'd call physcial evidence, but we must believe in the evidence for it to have any power. And as uncertain as that may leave us, it may just be an unfortunate reality that that is the only certainty we can have.
Based on that, I think that life has no reliably knowable meaning or purpose. If life has a meaning or purpose, we can only speculate on it, or coincidentally know it. But we can never be sure we're right.
Personally life has been for me a big inconvenience. Not terrible, not wonderful, just inconvenient, annoying.
I am not really into philosophy. I figured out a while ago that studying philosophy wont lead me to answers, only more questions. Intellectually I can not be certain of anything, intellectually I have no way to make decisions since I can not be sure of the validity of anything. So to avoid sitting still unable to decide if any action is preferable to any other action, I let my "ID" run the show. Or perhaps my "ID" always ran the show otherwise i'd have no incentive to stop sitting still and never being able to know anything.
My "ID" uses my superego to its own devices. What motivates me is simple. I pursue pleasure, satisfaction, and happiness, and I avoid unhappiness, pain, and other negative stimulation.
Now here is a big assumption: Death is like unconsciousness, it is simply a lack of experience. Now that is a big assumption. It is equally likely that god exists, heaven and hell exist, and that suicide is a mortal sin. However the more inactive a brain, the less experience is reported. Such as during resting sleep.
So assuming that death is the end of experience, that life has no knowable meaning or purpose or value for that matter, death doesn't either, and life is a huge inconvenience, suicide is the logical conclusion.
However I have what some would call a sense of self preservation. It isn't an intellectual thing. And as much as an inconvenience as life has been for me, cumulatively the sense of self preservation, the pleasure I experience, and the desire to avoid the pain of death, I do not as of yet have enough incentive to try something different(death).
And for myself and other people there are many factors I did not mention which makes life more or less valuable and changes the validity of suicide.
Now this doesn't really answer whether or not suicide is the right idea. But I think that given these things, people cannot be called stupid or ignorant or weak when they decide to take the gamble.