@Sandy731
I am sorry for your personal circumstances, but I don't think you understand how Airbnb works. When you make a booking, you are entering into a contract. The terms of that contract depend on the cancellation policy and it sounds like your stay comes under the 'long term cancellation policy' which applies to any stays over 28 days.
When you booked, the information about that cancellation policy was readily available to you and, by booking, you agreed to it. And yes, you did then tie up those dates in the host's calendar, preventing other guests from booking, from the moment you booked and, it seems, you are still tying up those dates if you have not officially cancelled.
The other hosts here have given you a good suggestion in asking the host to refund you for any rebooked nights, but the host can only do that if you cancel and thereby free up the dates on their calendar. Obviously, the longer you leave that, the less chance that they can rebook the dates and also they are not under any obligation to do so because you booked, agreeing to the cancellation policy.
When you buy an item from a shop or online, the refund policy is usually stated on the receipt. If there is nothing wrong with the item, but you just don't need it anymore, you still need to return it within the timeframe and according to the conditions listed when you bought it. You cannot sue the retailer because you didn't return it in time. You cannot sue the retailer when you bought a non-refundable item that was clearly described as such. I would advise in future that you take the time to read the cancellation policies before making a booking, rather than just assume that you are entitled to your money back.
You may not have stepped foot in the door, but it's a pretty naive assumption to think that cancelling your stay and expecting the host to refund you all of it, minus two nights, regardless of whether they are able to rebook the majority of the stay, is a reasonable offer. Most listings do not live in some kind of 'la la land' costing the host nothing. There are mortgages, bills and local taxes to pay. A lot of this stuff still has to be paid even if the guest doesn't stay, e.g. for utility bills here in the UK (not sure how it works everywhere else), you have to pay a daily standing charge for gas and electricity regardless of whether any is used or not. There may be people, such as cleaning staff and their families, who depend on that host for the income.
Your booking has prevented the host from covering any of these costs because, from the moment you booked, no other guests could even have seen those dates as available. The host could have lost out on numerous bookings because of it. They are also entitled to a livelihood and you have no real idea of their circumstances.
Again, I am sorry for your situation, but you cannot pass the financial burden onto a stranger that entered into a contract with you in good faith. If anything, you should be approaching your former employer for some kind of recompense and, if that was not part of your contract with them, well then that is something you might have considered before booking the accommodation.
Personally, I am always willing to refund guests above the amount stated in the cancellation policy if I am able to rebook the dates, but not if the guest refuses to cancel and continues to tie up my calendar demanding all (or most) of their money back when that is not what was agreed to when they booked.