You IC is pretty much right there with that assesment ... I would also toss in that being angry with you and baiting you into a conflict/fight also helps her out with her guilt. I mean who would leave a good guy? So easier to paint you up as an Ahole right?
As far as Custody .. yeah she will want that in order to benefit financially. Mine pulled that, even wanted a 75/25 till I too countered with the same 75/25 in my favor and suggested I could easily spill the beans on the 'suicide' threats .... (was just a bluff to get her to back WAY off on anything but a 50-50)
That being said ... she will use whatever she has to try and 'win' here ... she is not your friend right now. Those transcripts do not mean as much as you think ... just protect yourself ... get counsel from a L ... you can still have a L in mediation.
