What a complicated collection of diagnoses. I can’t tell you whether or not you have bipolar disorder. I can tell you that smoking marijuana every day is not helpful to any of your problems and may be making things worse. Especially since you are taking medication, it is essential that you talk to your prescriber about it to determine if the weed is interacting in any negative way with your medicine.
Besides the drug use, I think the borderline personality disorder (BPD) diagnosis impacts everything else — even your concerns about who to trust. For that reason, if you were seeing me, I’d be working on the borderline diagnosis first. The most researched treatment for BPD is Dialectical Behavior Therapy. I encourage you to research it and to look for a therapist in your area who has expertise in that technique. It will provide you with practical tools for managing and regulating the emotional responses that often cause you to hurt yourself or to be confused about who to trust in relationships.
I wish you well.