Your daughter could get Mediation regarding the matter matter in an attempt to resolve the matter amicably.
If this does not resolve the issue then she could apply for an injunction against her partner, especially if it is affecting her health. She can apply using the Form N16A (Application for Injunction), she could visit her local County Court and ask the Court Staff for a Court Form and Court fee, or print one off the internet.
However, in light of the situation as a whole, I think it may be advisable for your daughter to consider her general situation by seeking the advice of a Family Solicitor, especially in light of concerns of your daughters welfare.
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