Mom talking about killing herself?

Get your son from her and get yourself a lawyer. No offense, but this woman sounds a little crazy and she needs help, you need to keep your son from him until she is mentally stable. So get yourself a lawyer, get your son and get your ex girlfriend therapy. I hope things will be good soon. Good luck. Oh, and about your finace, explain the situation to her, if she loves you she will understand. The main thing you need to do is get your son from your ex girlfriend.