But yet, something is stopping you from offing yourself? What exactly is it?
And don't say inbred survival instinct. It's something greater than that.
The parts of life that bring happiness and pleasure (as well as other things) is what keeps people going. These feelings can be explained biologically. For example eating a nice meal when hungry feels good, and the reason is that biologically food keeps you alive. Sex feels good because sex leads to reproduction and therefore beneficial for the survival of the species.
People who commit suicide are either stuck in a situation that leads to no happiness such as terminal painful disease like cancer, being in a prison like existance. or a mental disorder such as clinical depression where the brain is not working properly.
Your genes contain the program that you operate on. All your genes want is for you to reach reproductive age so that you can pass the genes into your offspring. Your genes/dna are using your body as a temporary vehicle to survive and therefore equips you with certain emotions such as happiness and pleasure which help the genes in their quest for continued survival.
This is the reason we share 60% of our genetic material with fruit flys and 98% with chimpanzees. The genes survived over long periods of evolution, whereas the individual animals/humans have short lifespans which is just enough to pass on the gene.