Is this suspicious?

So, my husband has a job that is mainly men. But there are a few women.

He came in a couple weeks ago, constantly talking about this one girl. And then all of a sudden, he stopped bringing her up.

But now said girl is now a friend of his on Facebook.

She stays commenting on all of his stuff (except the posts of me and our kids)

When I mentioned something that she commented a week or so ago, my husband accused me of creeping her page and then called me insecure...

I'm trying to not let my mind go crazy but something seems a bit off to me.. am I just crazy?