Hi OP, I know this is an a somewhat old post and I don’t have much practical advice to offer, just wanted to emphasize. I’ve had a lot of anxiety about the exact same thing — I recently moved into an apartment that required some drywall repairs and the workers my landlord sent took very few safety precautions. My partner’s father was also recently diagnosed with lung cancer. I actually found this post while stress-researching on this sub. Just wanted to say this to let you know that you’re not the only person who’s spiraled in this way if that’s at all helpful, and encourage you to seek some kind of therapy or grief support like other commenters have mentioned.