Thanks for your question, and sorry to hear that you got fired. This topic is not really in the scope of the School of Herring, but here are some quick thoughts anyhow:

You will need to try to come out of this stronger than you went into it. But it's not easy. Typically, human beings go through particular stages after they have received highly disappointing news. First you may not believe that it is true. Then you get angry and start thinking of revenge.  Then you turn positive and try to go back and negotiate a different outcome. Then you fall into sadness of what happened. Finally you can come out of it with acceptance, balancing your mind and focusing on the future again.

At your next employment, they will look at you and assess how well you have recovered. The less bitterness you carry with you, the better a job candidate you will be for your next job. To be able to leave the bitterness behind you, I believe that you must let the stages that I described above play themselves out in their full force. Thereafter you can let go of them.

I once lost my job as CEO of a startup company. It took me weeks to get my peace of mind back. Once that happened, I jumped back into professional work. An investor who then invested in my next company said that one key reason for believing in me was that I had recovered so well from the devastation of the previous job.

All the best!

Marten