Horror stories are somewhat effective, but ultimately it is up to you.
It is my understanding that the physical addiction is stronger from chewing tobacco than smoking.
You have made the ist step by declaring that you have a desire to quit, but do you really mean what you say. Somewhere in your mind there is doubt and until you come to face that doubt and be secure in yourself and your ability to be stronger than the addiction, you will fail. It is not easy, but you can do it.
Darrell