AITA for telling my SIL she can leave Christmas dinner when she freaked out over tampons?

Okay, she’s not my SIL yet but I used it to make the title simpler. She’s my boyfriend’s borther’s girlfriend.

I (f28) have been with my boyfriend (m32, Ian) for 3 years. We’ve decided to host a small, early Christmas dinner. One of the people invited was his brother, Jake (m26). Jake asked if he could bring his girlfriend as she was all alone (they’ve been together for 3 months) and we agreed, the more the merrier. His girlfriend, Naveah (f28) seemed a bit timid but lovely. Naveah brought her 8 year old son (that we didn’t know was coming).

She seemed lovely right until she went to the bathroom, she came out shrieking,box of my tampon she in her hand, literally gasping for air in between her shrieks. I could barely understand her. Turns out, my box of tampons was visible (duuuh, it’s within a reach because hey, I need it monthly, why should I hide it and then look for it). She was going off about being disgusting, how could I be so shameless to have this in front of a child and other men and so on.

I looked at her in disbelief, I couldn’t believe she made a scene about a box of tampons, has she never been in a shop?

Anyway, I told her that my tampons stay where they are but if she’s so pressed, she can leave and go home where no tampons are present. She turned red, quite literally, her face was bright pink. Huffing and puffing, she dressed her kid and told Jake to drive her home which he did.

Jake didn’t come back but he called from her house telling Ian that I was the asshole. I was surprised to hear that Ian (my boyfriend) agreed with him. I thought he would be on my side. We were about to argue but I decided it wasn’t worth it and went to my office to cool down and think this through. Am I the asshole for telling her to leave?