it's all personal preference, you could just keep the note about how it's no one's fault. It doesn't have to be about your struggles.
Personally I'm not leaving a note, last time I premade a note when I was able to express all of my emotions about why I want to leave at a certain date, and my father, who I wrote about, found it. He tore out all the parts where it included him, all the parts that included my mother, the part where i said my family situation is the main thing driving my suicidal thoughts to CTB at a certain time, and blamed the note all on something else lol.
It wasn't even out in the open they dug through my stuff to find something against me that day and only found stuff involving them :), they didn't like that much I see.
If I could watch them after I CTB, i would LOVVVE to see what they come up with to tell my extended family members about why I decided to CTB