Duffert I am in a similar situation and soo confused. I have been in my relationship for 5 years but we were best friends for 5 years prior and left our marriages for each other. I often confuse her mood swings for drug abuse. I am losing patience fast and I know that is not good for her! I am going to seek help for myself in hopes I can gain control of my reactions.
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I am bipolar1, PTSD and GAPD. But I recently did the same thing to my wonderful husband recently. Because I had gone into a state of psychosis from being bipolar. I was on the same meds for 11 years and they had stopped working. I ended up checking myself in somewhere. Because it got so bad that I was having delusions. In my case that's what started mine with my husband. I would get her to her counselor and psychiatrist. If that doesn't help. Idk. Be in mind if they change her meds it will take awhile. So hang in there. My psychosis is pretty much gone and my husband and I have became even closer from our experience. We bipolar people are worth it just need a lot of help along the way. If you love her remember the in sickness and health vows u took. It's hard for us to understand too. It took me a couple of months to realize. And another month for my husband to figure out how to help me. Fighting makes it harder on her more the likely. Anxiety is a big trigger for me. I hope some of this helps. Good luck!!!! I'm routing for u guys!!!!
Is she being influenced b anyone or anything. I know it may sound silly but if she watches a lot of shows that are dramas or shows about guys cheating those thoughts could be being put in her head by that. Other than that if she is deep in depression she may need to talk to a therapist or you two seek couples therapy. I am sure this is a tough situation to be in epecially when you have done nothing wrong. Her insecurities are likely deep rooted and I have been in a relationship with a lady that was bipolar. I know what it is like to have to pay the price for wounds that were caused by other men. If you can find out what is triggering it you may be able to catch it in time.