OMG but please don't beat yourself up over this!
Back in 2010, my father had some sort of traumatic brain injury that resulted in him needing emergency brain surgery (he's now fine), and six months later, my mother had a stroke at too early of an age (recovering now as best as she can).
In that time, the amount of 'trauma' I was going through was something I couldn't put into words but was something I simply had to get through and move on through and like you, grieving, letting myself be upset and scared and depressed unfortunately never happened despite how poorly I felt.
It eventually all came to an unexpected head when I saw a psychiatrist for something else completely unrelated and for the first time in the safety of their office with nobody related to me around and nobody to judge me, I properly grieved and let myself feel-feel the near-loss of both of my parents in such a short time, the panic and anxiety that I had felt but never expressed, the anger and even bitterness at the sense of unfairness, and just OMGIT'SOVER.
It's so much to go through and though I didn't lose either parent, I know very well what it's like to have that initial fear of loss and my heart goes out to you for knowing what it feels like TO have that loss.
In my heart's heart, I think you need to grieve-grieve and I would recommend someone like a grief counselor myself. You need to feel safe and be in a nonjudgmental environment.
I know why you picked up those smokes and I don't blame you -at all- and that was brave of you to be honest when you mentioned that you might not be ready to quit yet.
It was and is a difficult time and it helped you to manage; if you want to get back off, I think and believe you can but given the things you've been through, maybe some professional help would go a long way to not just helping you through this, but also maybe helping you in general in the long run.
The problem with quitting something familiar that helps to keep your mind off of things is that you have nothing else to do the same, but maybe with some help from someone professional, they can help you brainstorm ideas that will work for you instead of the smokes.
I was never happier or more grateful that I ended up at that psychiatrist's office for something completely unrelated; I really needed that place and space and the feeling of safety he gave me to really 'let go' and grieve and just 'feel' without my 'I need to be in control because life doesn't wait and I need to take care of things' instincts kicking in into overdrive.
Wishing you all the best.