Should I worry?

So my SO has a best friend who is a girl. I am not the jealous type so that's not my problem. My problem is he tells her EVERYTHING that happens in our relationship. Not going to lie he's out of town right now and we were having some fun over Skype when someone walked into the room he was in. The family he's staying with has a girl his age and that's who walked in (not his friend) she didn't see anything but he told his best friend about it. He also apparently tells her about every fight we have and the fact we've had miscarriages. Should I worry?