This is very frustrating I can see, and I understand.

Good for you for taking the Vocational training. I'm sorry it didn't work out.

I have a few thoughts on finding work (I am unemployed myself as my PTSD and Anxiety just are too big a problem; but, I have a plan in mind when the time comes): Visit your local Mental Health Association. They ought to have a vocational counselor there to help you in such a quest. They will also have a list of jobs and employers willing to hire persons with mental health issues and needs. Visit your Unemployment Office. They can help you with selecting the best positions to apply for that fit your needs, training, and experience. They can direct you to programs that can provide training and experience you may require. Some of these programs pay you to attend. Here there are government programs that place you in on-the-job paid taining scenarios. There are also, as you have already experienced, temporary agencies. I believe that if you were let go from such a placement it was the fault of the agency for not better matching you to a position.

Be prepared to start in an entry level position.

If you have something you want to do, contact a business in that field and ask them what they look for in a hire.

These are just a few ideas that have come to mind.