Please, I would not contact your ex. She will likely suck you into her drama again and tempt you. If she is unmedicated, or the medication is not working, she is just bad news all over. Avoid her like the plague, she will only bring pain and suffering in your life. I'm sure she doesn't mean to, but that's the nature of her illness.
There's a reason you two were off and on again. I bet her emotions were all over the place, and she's unmedicated. You need more stability in your life.
I have a long time interest in psychology, specializing in relationship dynamics for 30 years.
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