Your dp needs to treat looking for a job as his job for now.
Cv, agencies, job sites, LinkedIn... Identify all the likely employers of his skill set in the area and check their web sites.
Network with all old colleagues. consider short term contracts, relocation,part time etc.
Then look for temporary work - driving, call centre, agriculture, etc.
Your job is to stay calm, have confidence in him and remain positive. He needs you to believe in him, he doesn’t need to be comforting you at the moment.
Look at how you can cut costs. Cancel all subscriptions, cut bills where possible, take one car off the road, reduce supermarket bills etc. No takeaways, holidays or new clothes. Work as a team to make the money last as long as possible. Consider going interest only on the mortgage.
And then celebrate together when he gets a new contract 