I feel for you, giving up was the hardest thing I ever did and I had to deal with my Dad dying and arranging his eventual funeral a few months later. I had alot of the DTs you described (I also suffer from GAD and depression) but it does get easier.
I didn't go cold turkey though I vaped for a year first starting October 2017 on a low strength of nicotine, I then used nicotine gum and sometimes patches before giving everything up October 2018, my Dad passed April 2019 but when he was really poorly in January it was hard not to reach for a smoke.
I don't miss it now but I did put on the best part of a stone since Oct 2017, (I did need to constantly have something in my mouth and food served that purpose alot of the time, I bought 2 bags of 120 full sugar chuppa chup lollies
) I also found exercising more really helped, jogging, zumba, bootcamp pilates anything you would find enjoyable and to measure your health improvements!
Its a battle but you can do it, and I will never touch another smoke again because I don't want to go through quitting again.
I also put aside the money I used to spend on smokes and treat myself (I could afford an extra holiday every year!), I'm currently pregnant but after I have the baby I'm going to get my teeth professionally whitened too. ;) The feeling of not being addicted is so worth it. X