Take it from me. Ignoring your mortality is a lot easier.
After that I was able to do 30-60 minute sittings at home and experience the associated change. If you're also a very cerebral person you may also need a similarly concentrated "boot camp" or similar to get to some base level.
In a similar vein, if someone has extremely weak physique, it's not really convincing when they claim that physical exercise doesn't work for them, as they did spend 150h at the gym machines ;)
I've wanted to do a retreat very badly. I would need to work to organize my current world to fit it in but it's something I have in the back of my mind.
You are not one but many, and the ego is truly the only thing that dies in death we fear.
I have a thing where I get weird anxiety ~18hr after I eat pasta, maybe you get something similar.
If your anxeity has a biological cause (ie excess cortisol or something), then modulating what you put into your body may help.
Or maybe you just need to accept that every moment might be your last and try to enjoy it. :)
It actually changed my life, now I can sleep and be like a normal person. I used to joke that I was a C-type person (instead of A/B) when it comes to sleep.