@Mesky0
I feel for you, that would ruin your holiday! This forum is for hosts, so Airbnb isn't going to respond.
From what I've read on here, when Airbnb say they're not going to help any more, they're not going to help any more. I don't see many positive options, given the host is not communicating
1. You could find out about getting a courier to collect, then give the host the details and she may just let the company pick up your bags. You will have to pay, I'm sure
2. You return to Madrid on a cheap flight and visit the host (probably cheaper than option 1), assuming she still has them
3. You find somebody in Spain who will do option 2 for you, then send your bags on (at your cost)
4. You look into how to make a claim through Spanish courts
5. You write to all the 'problem pages' in papers in the UK to highlight the issue. I think they'd be interested in the story - I expect most travellers don't realise how alone they are should there be a problem Airbnb is unwilling or unable to sort out
Good luck, and let us know what you decide to do.