Sonali Deraniyagala wrote a book about her experience through this tsunami. To be honest, the book wasnt amazing because of her writing style imo, but still a pretty good read.
I'm so sorry for everything you've had to go through and are still suffering. You are going to feel absolutely every emotion imaginable and then some because suicide is beyond devastating to those left behind. All I can suggest is just be honest about what you are feeling. Your feelings don't have to be logical or rational. You don't have to explain them away. It is ok to feel them and let them wash through you. It is ok to feel alone even if you are surrounded by people. A part of you is alone as your grief is unique to you. But you are right, another part of you isn't alone. There are many of us out there in this shitty club...It is ok to feel both.
Please read this famous post on reddit if you haven't about grief as a shipwreck and waves. I find it to be painfully true but also helpful to remind me that there are breaks in the waves and there will be more breaks...even if we can't see them right now: https://www.reddit.com/r/Assistance/comments/hax0t/my_friend_just_died_i_dont_know_what_to_do/c1u0rx2/
In the deepest stages of grief I found an odd connection to Sonali Deraniyagala when I read Wave. https://www.amazon.com/Wave-Sonali-Deraniyagala/dp/0345804317
She lost her parents, her husband, and two children in the 2004 boxing day tsunami. The book is basically a barely edited collection of her therapy notes. While her situation was so, so different from mine I still related to the utter devastation and complete restructuring of life that was required as well as her brutal honesty of the anger, bitterness, and pain of the whole process. I did not grieve like her, but I felt so connected just the same. I know not everyone can handle more devastating grief when they are grieving but I found comfort in it so I thought I'd at least mention it.
Please keep reaching out to all your support systems. I'm so proud of you for trying and still trying. Just asking for help or even speaking out is so much more than some can manage. I know you can't see it right now, but I see strength.