My wife is falsely accusing me of abusing her and our children and we are separating. What should I do?

I am currently living in the family home, in the process of separating and my wife has been accusing me of abusing our daughter, herself and our son. I am of the firm belief she has Avoidant Personality Disorder as a result of being born to schizophrenic parents and the victim of merciless bullying as a girl. The alleged abuse happened some months ago, largely shouting which I freely admit and a series of heated arguments. I punched a fridge, for the 1st and last time during one such and this is also being cited as an 'event'. We will be going for mediation next week and I am not sure what to expect. How can I make clear that she is, if not lying then, bending the truth to near breaking point and safeguard my relationship with my children?