This is a tough one… But what I’ve seen the elders around me do is that they meet with the deity and consult if whether the individual is right about their relationship with the deity.
Deities will always remember their lovers no matter how many they’re. If they’re not aware of her/him, then there’s a problem and you have to very gently break it down to them.
It’s also advised that if you have a new deity or entity in your life you have to test and see if they’re legit by asking your trusted circle of witches and by testing them too to make sure they’re not imposters.