Is Trust public in Ripple?
Trust must be public because other people can use it. I agree, this can be awkward.

I don't see community/private credit as a major use case for Ripple in the short term because of issues just like this. But I hope that in the future, and maybe even with changes in social conventions, this may change the way people think about money.

Look at how transparent people are now on Facebook. They publicly friend people and defriend them. So it could happen.