How do I approach his co worker?

My husband and I have been together for 10 yrs, married for almost 1. His female co worker used to come over when we were both home, now just comes over when he's home. She brings mutual co worker friends of theirs. The other day I had our little girl, stopped by his work to let him know I was taking her home, as she was sick. I intended on skipping my meeting at work. I had "rudely" motioned him over, not intentionally of course. He took it that way, as so did his female co worker...so he comes over, she walked away with an obvious attitude toward me...what is up with that???and how do I approach her, as I have already reemed my husband. I'm not threatened by her, I just don't appreciate the disrespect...The more I think about it the more mad I get. Any suggestions..?