18.—(1) In this regulation a “relevant relationship” is a relationship during the course of which, by virtue of any provision of these Regulations, an act of discrimination or harassment by one party to the relationship (“the relevant party”) against another party to the relationship, on the ground of sexual orientation is unlawful.
(2) Where a relevant relationship has come to an end it is unlawful for the relevant party —
(a)to discriminate against another party, on the ground of sexual orientation, by subjecting him to a detriment; or
(b)to subject another party to harassment,
where discrimination or harassment arises out of and is closely connected to that relationship.
(3) In paragraph (1) reference to an act of discrimination or harassment which is unlawful includes, in the case of a relationship which comes to an end before 1st January 2007, reference to such an act which would, after that date, be unlawful.
(4) For the purposes of any proceedings in respect of an unlawful act under paragraph (2) that act shall be treated as falling within the circumstances relevant for the purposes of these Regulations as determine most closely the nature of the relevant relationship.