Thank you for your question
My name is Clare
I shall do my best to help you but I need some further information first
How old are the children and why do you wish to stop her seeing them?
That is fine.
Who has had the day to day care of the chidlren until now?
What will the children want?
The law says that children are entitled to have a close relationship with both parents and the courts will enforce this if necessary
At 19 your eldest is an adult and can make his or her own decisions
Both of the younger children are of an age where their wishes will determine what time they spend with each of you - and there is no doubt that it should include overnight contact .
You should offer to discuss matters with your ex using Family mediation
choosing a mediator who also works with young people
Please ask if you need further details