There is no simple way to diagnose for bipolar disorder, it may take one time or several times before a psychiastrist or a trained professional comes to a diagnosis.
You've mentioned that her moods get really bad around here period and it does for millions of people out there. It could be Premenstrual Dysphoric Disorder (below are links that explain a little bit about PMDD):
She could have any of those things, depression, bipolar etc, but there is no sure way of knowing without a psychiastrist or a trained professional handling it.
What symptoms is she having that is making you suspect that she might be bipolar?
In the mean hand, I wouldn't mention anything just yet, I would do some research on PMDD, bipolar and depression before approaching her about it. Then suggest that you go see a psychiastrist or a trained professional together if this might make it easier for her.
Best on your search!
~~~ Olivia ~~~
"Don't let your yesterday, ruin your today"
"The moon if always full, think about it."
Dx: Bipolar I (mixed-episodes), PTSD, Anxiety/Panic Disorder
Current Meds: Lithium 900mg, Geodon 60mg 2x/day, Ativan 1mg
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