From Erin Pizzey's book 'Prone to Violence' which, although out of print, can be read online:
In examining why some women stay with violent and abusive men after having been warned that to do so may result in their death, Ms Pizzey wrote: 'the chaos, anarchy and drama of the violent relationships which they have lived through has created within them a special urge to continually relive the excitement of what they have left behind. The dramas in their relationships seem endless and in these conflagrations chaos reigns. Children in such a situation feel the ebb and flow of fear and excitement. Soon they grow from terrified unwilling spectators to active manipulators in the family war'
Although he used more subtle means than physical violence to control you, Waiting, the result has been the same in that you continually relive certain excitements of what you have left behind.
In additon, the dc were raised to be completely subservient to his will. His voice was the only one heard in your former household and your dcs were repressed to a point where their behaviour was unnaturally 'good' both at home and at school.
Unsurprisingly, after he was forced to leave your former home it became a case of 'the king is dead long live the king' as your eldest dc attempted to rule the roost in much the same way as his f had done. It would appear that you dealt with this by shipping him off to his f where there will be little opportunity for him to become anything other than a chip off the old block.
From what you have said, his attentions to your eldest dd once she reached the age of puberty were the equivalent of grooming and, unsurprisingly, after the departure of her f from the former family home, she aligned herself with him, became his 'spy in the enemy camp', and sought to undermine and flout your authority at every turn.
Having been freed from the suppressive effect of their f's presence, after assauging their fear that he would return the younger dc ran amok causing you to doubt your ability to exercise appropriate parental control over their behaviour.
Having become overwhelmed by the demands of dc whose corks had been popped and who were fizzing with energy, you encouraged them to go with their f on every possible occasion so that you could get some peace thus making a mockery of any objection you had to him having contact with them and enabling him to use this in his campaign against you.
The fact that he's broken bail and violently attacked you on numerous occasions without you having reported him to the police, together with you having withdrawn charges against him on several occasions, has enabled him to make you out to be a liar and may have contributed to the lifting of the non-molestation Order you obtained against him.
Your 2 eldest dc have become, in Erin Pizzey's words, 'manipulators in the family war', and in siding with him, you are effectively fighting him and 2 of his clones plus, of course, the 2 of your close relatives that he already holds in thrall to him.
And now he has turned his attention to your younger dd who, coincidentally, is also approaching puberty.
You fear that if you use the police to return her to your home against her will it may turn her against you and may cause the Court to look unfavourably at you for involving the police in this matter.
However, if you leave her with him, he will undoubtedly poison her against you and, given that you gave your consent to her spending one night with him in flagrant disregard of the Court's wishes, the Court may take the view that any objection you may have to your dc having unrestricted and unsupervised contact with their df is unfounded. Should that come to pass, he will make good his vow to have every one of your dc off you unless you wise up and fight him tooth and nail.
His previous behaviour to the dc was such that, even though they dared not say a word out of place in his presence, they craved his approval and were jealous when dd1 became his obviously favoured child.
By morphing from tyrant to fun daddy who let's them get away with things mummy wouldn't tolerate and who, as no doubt he's explained while making much of them at his local, was only tyrant daddy because of mummy's real or perceived faults, he's reinforced the control he already had over them and further convinced them that black is white if he says it is.
You've had chance after chance to expose this man and every support and encouragement to keep him out of the l Can you not see him for the monster