Hi, A person with bipolar and diabetes can take insulin. Having stable bgl's and stable bipolar is the best outcome for a person. People with Type 1 need insulin. Type two diabetes can be controlled by a number of medications. Capsules and Injectables. When type two becomes unstable on other medications insulin is an option. Information in regards toi BGL's should be obtained from your doctor or diabetes nurse.
Or have I read this wrong and your gf wants to commit suicide by overdosing on insulin? Apologies if I got this wrong.