First of all thank you all so much for all your support over the last couple of days - i'm am beyond appreciative and it helped so so much!!!
Finally spoke to the wedding coordinator today after all the previous drama - have basically spent the last 2 days sick with worry that the whole day was ruined!!! Wedding coordinator was back today and phoned me.
Basically it's going to be ok!!!! They have got in new builders and have a guarantee that the new building will be finished - if its not they will be paying a vast amount of money to put the other wedding up off site ie no where near the main hotel. The other wedding is arriving at 4pm and having welcome drinks on front lawn - this is well away from us as we'll be in restaurant at that point and wont be able to see or hear them. They'll be moved up to their building before we have finished the meal - after which we'll never know they are there.
They have no access to the pool/terrace are which we are using and at no point will any of our party, let alone us, be in contact with them at all.
She was extremely apologetic and genuinely sounded upset at what had happened in her absence (bet she wont be going away in July again!!). She can't believe we were even contacted and said it was their problem and not ours.
So looks like the day will be as i've planned and i can relax and enjoy the build up again!!! Even if worst case the building isnt finished they'll be moved to another venue so we will not be effected.
No offer of any compensation for the stress though but at the moment i'm just ecstatic i'm getting the wedding i've planned!!