I agree. Suicide is never right, but if your brain chemistry goes hay-wire, and neurons bouncing around where they shouldn't be going - there cannot be anything worse. You cannot run, hide, or escape the pain and utter despair. And if your brain is keeping you from running to Christ ... I cannot imagine the hopelessness. And with Satan whispering in your ear to end the pain - sure.
Suicide is never right, but like you say, I can only pray for the loved ones that are left behind, and hope in his/her final moments they were able to see through the haze and find the Rock and hold on to Him.
Your words are so true and brought tears to my eyes. I lost a close family member to suicide.
I choose to believe that, as he was passing, his illness fell away and he ran straight into the Arms of our Savior.