You asked for opinions so here is mine...
in my JW days if I received that message, I would delete it without considering one word of it.
why?
you sound very angry.
you cover too many points.
I would say dont send it.
IF you decide to send something pick the 4 or 5 sentences that most make your point. Send just that.
All the best to you whatever you decide. I know its hard dealing with family.
They push buttons we dont even know we have!