The Court of Appeal has ruled that it will not necessarily be unlawful discrimination for a manager to mention an employee's homosexuality to others where the employee has already made it public. 

An employee had 'come out' to colleagues at another office and had not asked them to keep it confidential.  Following his move to another office, his line manager made references to his sexuality to his new colleagues.  The Court decided that this was not unlawful  - there was no intent to harass and, although the comments had caused the employee discomfort and upset at not being able to release the information in his own way, this was insufficient to amount to a humiliating environment.

An employee who puts information into the public domain must accept that the information may be discussed by colleagues.  However, much will depend on the context - comments could still be unlawful depending on to whom they are made, in what terms and for what purpose.  (Grant v HM Land Registry, CA)