After 15yrs of 175mg amitriptyline nightly I had to stop 3 weeks ago, no sleep since

You cannot stop such a dosage as high as what you are on cold turkey. That is dangerous. Speak to your dr again or get a 2nd opinion.

I agree with Stephen, your brain has been used to a very dose for 15 years and you are bound to have a severe withdrawal from this. I assume your neurologist thinks the Amitriptyline caused your seizure yet it appears from what you say she hasn't explained things properly to you or taken into account that after having the shock of a seizure, followed by sudden withdrawal of this drug it may have been wiser to talk you through this and the effects you should expect, sleeplessness being only one. Do talk to your GP and get as much information as you can followed by full support and/or a changeover to another medication that could help you. I wish you all the best and do let us know how you get on

I'm also surprised that despite the heart risk that you have not been allowed to come off gradually. My friend has heart problems for years and yet her GP allows Amitriptyline on a smaller dose. I know we shouldn't draw parallells because all cases are different yet it is a small risk to allow you to taper off. You are obviously suffering and I guess 16 days cold turkey has already passed but I doubt you will find anyone out there or on here who has gone through the same thing. My feeling is that you should get a second opinion even at this late stage. There must be something you can be given to help you through this awful stage because lack of sleep and anxiety are just as harmful. 

Obviously your doctor is an arrogant idiot that never has to suffer in her life. I've been off the taper for 4 months now and still can only sleep maybe 4 hours at most. For the first 2 months I were not able to sleep at all.