AIBU to be gopping mad at this woman who posted my DCs party invite on social media!?

[VodkaVomitANDPoo]

I made some daft invites to look like magazine covers for DCs upcoming birthday to use up a load of old photo paper.

I found it odd that I was getting text message acceptances and requests to bring siblings from mothers of children I had never heard of- when quizzed the same name came up and a mention of a Social Networking site.

It turns out one of the mother's of a child in Dc's class took a photo of the invite (which had date/time/venue)on her wall and posted it on FB under an event (wtf?)

I've hired the venue out privately and am panicking the party will be ruined, we will end up in the local paper because 200 kids turn up wanted to be entertained and fed.

I asked the mother directly and she denied it and I have no proof (screen shot etc) although I am STILL getting texts

DC will be heartbroken if I cancel I just do not know what to do for the best. The last thing I'd want it having to stand by the venue door for 3 hours instead of joining in a celebrating a birthday- It wouldn't be so bad if it weren't for the fact my child will be 7 but this is the first time we've ever held a party.

Any advice on how to handle would be greatly appreciated.

When I was very little, my mum was involved in the WI - and the local branch Chair's surname was Benn-Gough - and I decided that this was an excellent swearword, and used to go round saying, "Oh Bengoff it!!" - in a very obviously sweary way! Mum was in constant fear that I would do it in front of Madam Chairwoman, and she'd be drummed out of the WI!