I think a rights violation is making it impossible for an individual to express that right. Blackmailing me doesn't violate my right to speak, it violates my right to not have physical harm threatened against me.

I think you should really rethink this one. Blackmail (we'll just talk about true information not extortion via threat of force) is wrong. But it's not violating a right to secrecy, it's that the threat is being used to infringe on some other right.

Or imagine you have a right to speak/vote/get an abortion/whatever. And I (wanting to prevent you) let you know I will stand in your way in the street, obstruct you, cost you an hour of your time. You'll get to do it eventually, I'm just making it awfully inconvenient. This doesn't violate your right? You'd say anti-abortion activists (or anti-Republicans-voting, or whatever) who make it super inconvenient aren't violating anyone's rights at all?

I had laid out my thoughts on this matter on the bit where I exceeded the character limit and I think you might have missed it, but here goes again

I think I never got this (or didn't notice it if I did).

One is not not morally obligated to help any other person".

To me it's obvious that there's a matter of weighing benefits/consequences, and that you do have a clear obligation to call 911 at no real cost to yourself whereas you have no obligation to risk your own life. Why is this not the conclusion you draw?

Lets make this super personal. I just saw a commercial that stated for $.43/day I could feed a child somewhere.

That one's less personal than the car examples. You are physically farther; there's no urgency; there could be millions of people who could help the kid but you were the only person who could help the accident victim.

I don't think this point is vital to the adultery discussion since it's about harm rather than helping others (unless it's a super weird adultery example). But I do think your obligation to help others is proportional to a lot of things. Your relationship to them, the extent to which you are the obvious person to help, the extent to which others could help, the risk to yourself, the harm to them, the extent to which it was your fault in the first place, the extent to which it was their fault in the first place, etc etc.

So at the most extreme example, you take your mom hiking, convince her to cross the river on a log instead of the bridge, and she breaks her hip. You could call 911 or help her back, but you'd get your inheritance faster if she dies in the woods. Any moral obligation to help her?