[HumblyTossed]

Best advice I've ever been given: Wait to worry. If you can't do something (anything) about it immediately, don't worry about it.

Using your example, you haven't decided to restructure your roof, so there is nothing actionable you can do right now WRT your neighbor, so don't worry about that.

[teekert]

Funnily enough I'm really good at this at work and always tell my colleagues this. They often find me ridiculously relaxed in difficult situations. But at work, if I can't change something I don't worry (when a boss asks me 10 min before an important meeting to present it, I just wing it because the thought "They can't expect it to be perfect with only 10 min prep time", makes me very relaxed. But the thing is, with the small things I do worry about at home I often can change something. I can prevent the neighbor to be bothered by my new roof or at least I could talks with them about it. Of course, that only makes sense when we actually change the roof... But then again if they know we may change the roof they can also keep that in mind... At this point just tell the neighbor, but what if we never change the roof and he changes his plans based on my remark? I'd better move somewhere else quickly...