Before the stuff that I'm writing now (sci-fi musical, obviously not serious), most of my output was deeply personal. I found a good way around the inevitable worries of writing about real people, and them hearing it, was to write personally but combine relationships and people in to different characters and situations. I don't imagine it masked what I was talking about amazingly, but writing about something that's an amalgamation of different experiences is easier than writing about something so plainly.
If you have to write an entire album about someone,or about a failed relationship (I think we all do, at some point), another good thing to do is to make it about an imaginary character that you can treat any way you want in your songs. I wrote an album about an imaginary person at an imaginary party that was actually about two or three relationships, and lots of experiences, but I wacked them all together in to an unrecognisable package.
If you have a lot of traumatic, upsetting, confusing or downright depressing shit to figure out, writing about it is amazingly therapeutic. But it goes without saying that writing about it will also be traumatic, upsetting, confusing and depressing, too.
