It is people taking personal responsibility that commit suicide. If a person is following God's will they would be constrained from doing so by faith that God knows what He is doing.
The suicidal person does not go to Hell simply because of their sinful act but there is a definite downside to suicide: God does not have to allow a person a new life if he shows so little regard for his previous life. That would be OK if the person went to Heaven but my guess is that the majority of suicides do not. My cousin was a suicide and I believe that her ghost was around long after she died and may still be around. Perhaps the saving grace for her will be the general resurrection of the dead.
The vessel of clay with intellect is Adam.
That being said, make Adam a creature with choice and responsibility.
Whether he chooses to exercise it or not, is his choice.
A suicidal person, having intellect, having a choice, is responsible to self.
The choice is one of responsibility or to give it all up.
Circumstances, environment, upbringing, belief structure all have a bearing on personal responsibility, not to exclude individual character.
Loss of hope in all of the above is to loose hope in living.
Trusting in God gives hope to a trouble life, giving strength where human will and strength can not bare.
I see this life as a one time privilege.
Make the best of what is given, even if it is but a little bit.
Blessings, AJ
