Last night, my brother, who is in the process of possibly getting diagnosed with schizophrenia, stole my car and went to a club. He returned of course. He used my credit card to get in/possibly drink/ and get some cigarettes. He doesn't yet know I know. He recently switched meds which he confided in me the previous day that it made him very nervous.

How much should I hold him accountable? What should I do? Advice PLEASE.