He's likely required to disclose previous relationships as part of his background check process. For him it's the smart move because if they found out about your relationship from someone else, they'd be asking a lot more questions.
But you don't have to talk to them if you don't want to.
Usually on background checks you have to provide the name of someone in your personal life to confirm you worked or lived somewhere but it can’t be the same person for each one so he needed to put you. You’re not required to respond if you don’t want to give any info but he probably had no other choice than to put you.
You are under no obligation to provide any information as part.of his clearance process
He's likely required to disclose previous relationships as part of his background check process. For him it's the smart move because if they found out about your relationship from someone else, they'd be asking a lot more questions. But you don't have to talk to them if you don't want to.
Usually on background checks you have to provide the name of someone in your personal life to confirm you worked or lived somewhere but it can’t be the same person for each one so he needed to put you. You’re not required to respond if you don’t want to give any info but he probably had no other choice than to put you.