Fight cancelled due to your stupid national strike

Hey all, I am an international student here in Belgium. Me and my friends thought it would be a good idea to take a break from our studies and book a new flight on 31st of March from Charleroi to Salerno (Italy) for a couple of days. For your information, we booked the flight tickets starting from January and have already booked a small apartment. Then in the last minute (4 days before the departure date), we get a notification that the flight has been cancelled due to the national strike. This is not new, but given the circumstances and last minute warning, what can we possibly do? Ryanair does not even let us change a flight which is totally absurd. Has anyone been in a similar situation or know how to get around?