My DH and MIL have always had a poor relationship. I think she has mental health issues, inc anxiety and a need to control situations (but maybe that's because she's my MIL!). She frequently criticises our parenting and has questioned even our relationship, saying I treat my DH like a doormat as I work full time while my DH looks after our children (who are 1 and 2). She apparently suggested I was cheating on my DH when I had to go away for 2 nights on a work conference!
We have never and would never stop our DC seeing her. We also don't say anything negative to her or about her in front of our DC as we don't want to spoil the relationship they have. However, we're keen to minimise her poisonous and negative vibes. For this reason, DH agrees to see her in public places while I'm at work and has said she's no longer welcome in our house as she is so negative and argumentative in front of our DC. She usually sees them every 1-2 weeks for the afternoon, either at park:play area/ restaurant, usually within a day or two of her asking. Previously, MIL looked after our eldest as a baby one day a week but this became less frequent due to her own commitments (she doesn't work, but often cancelled as she had a gym class or doctors appt on the days she was due to have her). Occasionally, she looked after our youngest until he was approx 4mo.
MIL has said she wants to take us to court for more access to our DC, but suggested mediation first which we have so far declined. We've declined it mainly because she hasn't said exactly what she hopes to achieve although suggested that she wants my DH and DC to get to her house more often. She refuses to be specific and has even suggested she won't put anything in writing (even a text) without legal advice first. She also said today that she has 'evidence', i.e a photo of them in their car seats without the straps fastened correctly-I have absolutely no idea what she's referring to here but can't help feel she's trying to build some sort of case against us for being somehow negligent!
Should I accept she's barking? Does she need help-seriously? Is there a chance our DC might be forced to go there without our supervision? Or worse? Any advice would be much appreciated.