Suicide is a selfish act, and all my belief would point to me saying no.
However, there are grey areas too, I mean like euthanasia, is that the same? Because it legally happens to a degree, medical professionals can give lethal amounts of morphine if the person is suffering enough, to dose is obviously there just to ease pain but with the known affect that it will decrease reparations and eventually the person will slip away. Is that wrong? What about a non-cancer terminal patient? How about parients who are slowly dying of terminal conditions which cause pain and distress? I once had a patient who went to Switzerland to end his life, he was slwoly dying and would regularly chock on his own spit so his wife had to watch him 24/7 along with raising her 4 kids. he had totally mental capacity but no physical capacity, i don't know if its right but would I like to live like that? No. I dont know what I would do but I know I would consider ending it if i could.
What about people who are going to die in situations like on the titanic, your stuck inside the ship, no way out and its filling with water, you will die. you have a gun, do you end it yourself or slowly run out of air/drown? Again don't know the answer but it certainly would cross my mind.
Those who tend to commit suicide jumping off building etc. are desperate and not of sane mind, i do think its selfish though.
So I think its complicated and wide reaching. From a religious stand point is it wrong, but i find the topic inst black and white so its difficult to give an answer.