domestic partner of a person means—
- a person who is in a registered domestic relationship within the meaning of the Relationships Act 2008 with the person or
- a person to whom the person is not married but with whom the person is living as a couple on a genuine domestic basis (irrespective of gender), taking into account all the circumstances of their relationship, including any one or more of the matters referred to in s35(2) of the Relationships Act 2008 as may be relevant in a particular case