Let's say I'm called Jane and DH is called John.
Background: I would say my MIL is narcissistic and my FIL is her enabler. A weird couple: they socialize with no one at all except me and DH. Their other son is abroad. They talk to relatives on the phone. They are clearly envious of DH and I having PhDs (like it's a big sodding deal!) because they failed their degrees. They mock us constantly and say nasty remarks each time we meet. They claim that we hate them when actually we invest hugely in our relationship with them: nothing is too much for us. They are not nice people and are passive aggressive in subtle ways. E.g. DH is hugely conscious of his dental problems and is waiting for treatment. They gave him a vampire costume as his birthday present, the bastards. They hate each other and seem jealous of our relationship: DH and I really are best friends. They are constantly criticizing us, yet can't stay away from us. The first time I met MIL she was shit-faced in a luxury restaurant screaming 'my son's a bad son! You're a silly cow being with him!' He is a wonderful son to her. I try my best to be a friendly, caring DIL even though I can't stand my PIL. DH wants to disown them but can't because they are family and he is too lovely for his own good. I could go on and on.
Short story: DH and I have been together for many years, married last year in secret (then told them afterwards). Last week, MIL referred to me on the phone to her cousin: 'John's here for dinner. With his friend, Jane'.