Her agents and/or "people" are probably the ones doing the twitter & Facebook to promote her career.
I know of at least one gay woman who is atheist... nicest person I've ever met.
I don't think it's a hoax. Some people can get very..involved in superstars' lives and even in fictional characters to the point that they are very real so it's not a huge leap to see someone go down the path of attacking a relative be it child or parent of a 'hated' person.
What next.. hate mail/death threat to a 5 month old baby or a animal...?