I know it’s a huge hassle, and requires a good internet speed, but each and every time this has happened to me I ended up fixing the CTD events by doing a reinstall of the software. Including the initial installation, I’ve installed Flight Sim - from scratch - four times now.
When I do that, it has fixed the CTD events every single time - until the next patch or update. 
I’m just trying to “roll with it” and keep a positive attitude. The experience is a lot of fun, (not the reinstallation) and - for me - worth the hassle.
If you have the MS Store version of the software, you can follow this guide to accomplish the task.
Good luck and happy landings!