My long-term partner says he wants an open relationship. I understand why, but it feels one-sided. What should we do?

‘Not all open relationships are about casual sex or kink,’ writes Eleanor Gordon-Smith. Painting: Venetian Lovers by Paris Bordone. Photograph: Heritage Image Partnership Ltd/Alamy

My partner and I have been together for six years. At the beginning of the relationship we talked about monogamy, he’s never been in an open relationship but likes the idea of being in one, as he’s cheated in the past.

I understand how love and relationships are never black and white. My partner has brought up the possibility of opening up the relationship on and off and reminds me he’s always wanted to explore this.