[Gurdit]

The reason I liked the suicides is because they're well presented. The recurring curse of October 22 is very well brought across, in my opinion. It's a good way to pass on the "inheritence".

But I do agree with Jon that passing it on as an inheritence after a natural/unnatural (but not willed) death wouldn't have been a bad idea either. I did find some small hitches while reading it... possibly a misplaced word or something. Let me try to peruse the text again and try to locate them.

Father went to West Point and though he was never what one would call a great student, he seems to be able to get the right people to notice him at the right time.

Switch of tense from past to present.

make a run for the Senate, which with the help of grandfather's connections went swimmingly.

Perhaps a comma is needed after "which" -- "for the Senate, which, with the help of grandfather's connections, went swimmingly". I also personally found the word "swimmingly" peculiar, but that may well be my personal taste.

I'm sure grandfather would have been equally as proud if he were still alive.

I don't think this is grammatically correct. I think it should either be 'just as proud' or 'equally proud'.

that school seemed a breeding ground

I think there is a sense of incompleteness here. I would have put something like "that school seemed to be a breeding ground" or just simply making it "that school was a breeding ground"

he was the kindest, but most driven man you could ever meet.

By using the word "but" here, you seem to be implying that generally, one can either be kind or driven, and to find a man who is both is an exception.

of the infected and dieing.

Perhaps that should be "dying". The continuous form of "die", I believe is "dying".

I used all the families resources

family's resources? In case you meant to say that you used the resources of all the many families, you would put the apostrophe after the s - families' resources.

not has not know in a millennium,

A missing "n" at the end?

Once your great grandfather had used this machine to make a perfect diamond,

In sync with your sentence and what you want to convey, I would suggest putting a comma after "Once"



And now some final thoughts:
I notice you only spend like 2-3 lines per character describing the turmoil they go through. You must remember that you are writing the letter on behalf of a man who is at the end of his days, voluntarily. He has chosen to commit suicide because of the weight of the guilt on him, as you say. He should be very emotional, yet I find his writing calm.

You could also perhaps spend more than a couple of lines describing their turmoil with emotion seeping in.