I, too, live in the West. Pretty much as West as you can get in the West, in fact: California, not far from San Francisco.
What you say is not reflective of what I've seen firsthand.
And therefore it should not happen to her.
If an adult woman, without pressure from her peers, fears of being disowned, or without the influence of drugs/alcohol (which shouldn't be a problem for Muslims anyway), chooses to get circumcised, then it's fine. Her body, her rules. But it should be her choice, and hers alone, and no one else's, not even her family's.
There's other ways to protect against STIs such as HIV. Proper sex education, for one.
You first.
I don't think you know what AIDS is, or its causes. AIDS, first of all, is the condition that results in infection by HIV. HIV can be transmitted through bodily fluids, such as those excreted by the sex organs, but also blood. You can get infected if an infected person's blood gets into yours. Effective prevention doesn't have to involve circumcision at all. Education is the best preventative method.
Agreed. Specifically, the women. They should not be circumcised while infants, or any younger than what would be considered a legal and informed adult in a given culture. As adults, if they wish to, that's their choice.