Hello And Welcome
Need to ask a couple questions.
What version of graylog are you using?
Could we see all your configuration made to set up HTTPS on your graylog server?
grep -v "^#\|^$" /etc/graylog/server/server.conf | sed -e "s/#.*$//g"
This might be a couple different things, maybe a configuration error or permissions.
Have a look at this following link maybe there is something in there that may help you out
I do feel your frustration, I also went through the same thing and many other here also. I know that everyones environment is a little bit different. What might work for one person may not work for another.
EDIT: I just seen you tried to show your log file, maybe just post it here and edit prior.