Can the most sane well behaved person turn into a killer if pushed past their breaking point? deep down we all can snap to the extreme.

Sort of. If you are under stress or are being pushed, you ought to consult a psychiatrist. Do not let it deteriorate to the point of no return resulting in violent action. Have a healthy diet, exercise 30 minutes/day, drink plenty of water daily so your urine is mostly colorless, have safe sex, no tobacco alcohol weed or street drugs. For nutrition: http://www.choosemyplate.gov/.