DDD, with all my heart I wish you the strength to do this. Goodness, twelve years is a long time.
I also did cold turkey, almost three weeks ago, after yet another angioplasty and stent. I am finding it unbelievably hard, and I am in a very bad mood most of the time.
My cardiologist said to me that after two days, the nicotine is out of the system, and it is not the physical addiction to the nicotine, but it is in the mind. I'm not sure she's right, but that's what she said.
I try to use logic and speak to myself, that I want to live to see my greatgrandchild (expected in about four months), and I have had too many blockages of 90% and over, and I just can't push my luck any more. But it is soooo hard.
Good luck to you -- I'm sure you can do it. If you did it once, you can do it again. I will also do it. At least I have more cash money in my wallet than I used to!!
Love, Esther