Hi Lazula, welcome to SR
Some good advice and encouragement on this thread.
I don't know about social work but is it possible for you to get any help or support from your Department? It's just that you might be in the one industry where, at least in theory, they should be supportive of your situation.
If your workload is too great maybe you can get it reduced or is that just pie in the sky on my part? A burnt out social worker is no use to a department and they should be able to recognise that
Congratulations on acknowledging you have a problem. That's a good start