Oh I’m so sorry to hear this.
Disney is usually decent about the tickets. As long as they haven’t started to be used (by entering the parks) then it’s extremely likely they’ll let you use the credit for a future ticket (even tickets bought via 3rd party vendor). I’ve done this a few times now.
Make sure to keep all your records, especially the ticket number. After a ticket ‘expires’ it might no longer show in your account. Keeping all the related info on hand is the best way to make sure the CM can help apply it toward a new ticket.
Even though the fine print sounds very strict they normally allow you to use the amount paid on a 1 ticket to 1 ticket basis. They won’t refund the price difference if the new ticket is lower cost, so it’s best to use toward similar or more expensive ticket.
Some of the brokers have given refunds in certain circumstances. Could be worth a try? They might even let you change ticket dates? Not sure. But even after buying thru broker, Disney will let you use that credit toward a future visit ticket through them.
For ticket purchased through Disney, they have in rare circumstances issued refunds but that’s more like a pixie dust decision I think.