I think if you don't want to loose her covert actions are not going to help. Families interact in a circular fashion and when one member has behavioural problems or depression usually all the family are implicated and a family therapist can help resolve matters. Family therapists also support family members through family breakups. See;-
www.aft.org.uk/home/familytherapy.asp
As far as residency is concerned there is a no order principle and courts will only make an order if it is in the best interest of the welfare of the child to do so. When deciding the case, the Court will apply the "Welfare Checklist", which is a list of the criteria the Court must consider when coming to a decision. It includes:
"(a) the wishes and feelings of the child concerned in light of the child’s age and understanding
(b) the child’s physical, emotional and educational needs
(c) the likely effect on the child of any change in their circumstances
(d) the child’s age, sex, background, and any characteristics the Court considers relevant
(e) any harm the child has suffered or is at risk of suffering
(f) how capable each of the child’s parents (and any other relevant person in relation to whom the Court considers the question to be relevant) is of meeting the child’s needs
(g) the range of powers available to the Court."
The biggest obstacle to a fathers’ being awarded residency after separation is the established patterns of care and relationships during the marriage. Things such as the child's perception of which parent is their main carer and who did the nuts and bolts of parenting are important.
Also family courts aren't criminal courts and there is little interest in divorcing parents slagging each other off, it's all been heard before. What they look for is a parent who is able to cooperate, can put their differences aside and is prepared to work together with the other parent for the benefit of their child.