Well look at is this way. You're assumably taking medications to stabilize your mood.

Alcohol is a depressant. Being bp II you apparently experience more of the depressive side of manic depression. Therefore, the alcohol is working against the mood stabilizing drugs.

Most of these drugs are processed through the liver. So is alcohol. So when you drink on your meds you are making your liver work double time, and the risk of liver damage goes up considerably.

Weed affects everyone differently, but for me its a mood stabilizer, which is your ultimate treatment goal.

Cut out the alcohol for sure.