My boyfriend just recently keep sending pictures of myself back to me sporadically. Why would he do that?

You just asked this question here.
https://www.askmehelpdesk.com/dating/relationship-739470.html
There is no need to start another thread. We don't know, ask him.

Asking him directly may have the right answer.

Maybe he thinks you forgot what you looked like??

Maybe he was supposed to send them to someone else?