Monna - I am so sorry for your loss and I am uber impressed with your ...uh - you know, just dealing with things! Going to work, getting on with things, and most especially, starting this blog with the thought to not only help yourself but also others - and that it could become an income source for you, too. Wow - that is just really impressive, as I don't do well at all with grief and/or sadness.
Here's my opinion on the whole thing, which seems to be far different from everyone else. LOL Since it sounds to me like you've lost your husband fairly recently, on the one hand - and also because, you have expressed concerns for the ethics of this venture - my suggestion is to just let it flow from you, to start out with.
Don't worry about keyword research, don't worry about who your advertisers might be, etc etc
In order to have this project be truly organic, just post. Just post.
If you're having a bad, sad day - post about it. 'Write yourself' through it. If you're having a together day and you've found something that is helpful to widows/widowers, post about that.
Just let it be truly organic for a while, without thought of how it's going to measure up to be a business.
Kind of like a painter or a writer (Deb, you can chime in here) goes through their creative process...just let it flow....then when it's nice and meaty - you can add more stuff that has more of a monetization-centric focus. And you can also go back and re-work old stuff to make it further benefit you.
The posts on my blog with the most traffic are the ones that just came out of me, with no monetization strategy in mind. Drives me crazy sometimes, but, it's true. I plan on going back to them, though, and now adding in stuff that might benefit me - or taking those certain topics and expanding on them, and linking back to the original posts, etc.
Anyway - that's my 2c