Dear Friend,
Please get help for your bipolar disorder. You need to focus on your health right now, not getting into a lifetime commitment with a volunteer publishing house disguised as a religion.
I was in this religion the first 56 years of my life and I know what I am talking about. The guilt feelings they will produce in you, making you feel inadequate will do you no good.
I have many friends and relatives who have bi polar and anxiety disorders and they have all improved since leaving Jehovah's Witnesses. The constant stress of meeting and assembly attendance plus getting in time in field service is not good for anyone.
To thine own self be true. God is not going to be mad at you for not joining a cult. Remember that.