My understanding is that you can't sue your ex for emotional distress.
So unless he committed domestic violence or child abuse (or perhaps a criminal offence like deprivation of liberty?), then your remedy will likely be in the Family Law Courts where you can put forward your arguments and evidence showing he has not done the right thing (and such actions caused you and your children emotional distress, which is not in the best interests of the child - which is the paramount consideration of the Family Law Courts when making Parenting Orders).
As I said above. I think the remedy lies in the Family Law Courts. I imagine it would be even more costly and stressful trying to sue for money from him in a separate action when that is actually what would be considered in the Family Law Courts (unless he committed a specific offence, which you'd need to get a lawyer's specific legal advice on).
Happy for other forum members to add their thoughts.