There are many reasons why a mother should want the children to hate the father.

I found this list at this site, which will be add to my list soon. After reading the list, ask yourself how many does these apply in your case.

1. The mother wants to start a new life and wants the father out of the way. She may be more successful than he is. He is seen as an encumbrance.
2. The mother wants money/property from the father and uses the children as bargaining pawns.
3. The mother hates the father and uses the children as weapons.
4. The mother is possessive and wants all the childrens love.
5. The mother is jealous of the love/gifts the father gives the child but not to her.
6. The mother cannot cope with her own life. Contact with the father in any form is difficult for her. It is a common statement by fathers that the mother suffers from depression. Sometimes PMT, when rows are likely to flare up over minor incidents, and lead to greater hostility.
7. Disappointment. She feels he is unworthy to be a father and doesn’t deserve the children.
8. The mother is egged on by other women hostile to men. Typically if she is in a group of single mothers.
9. The mother uses access to control the children (if you don’t behave then you can’t see daddy).
10. The mother can’t compete with the father who may be able to give the children more treats in the short time he sees them. The children may boost him at her expense, and typically demand more from her.
11. The children may be the only aspect of control the mother has, so uses it to boost her own esteem rather than for the interests of the children. This is the power motive more commonly seen in men.
12. The mother may still like the father and uses the children as a means of controlling him.
13. The mother may be punishing the fathers new partner indirectly as the father may know that he could see the children if it wasn’t for the new partner.
14. The mother may be independent and never wanted a man around anyway apart from fathering her children (entrapment). Or she may have gained independence during the marriage and now wants to exploit it.
15. As often quoted, the mother may see children as a way of getting a house, welfare money, and other benefits. The father was always incidental in the matter.
16. Some women actually believe that men are not interested in their children.
17. The mother assumes hostility by the father towards her is also towards the children, so ‘protects’ them by keeping him away.
18. The mother has a different lifestyle to the father, and does not want the children to copy his way of life.
19. The mother may have no family of her own (typically foreign wives), whereas the father may have a family. The mother regards the child as ‘her family’.
20. The mother may become emotionally dependent upon the child, and regard any affections the child has for the father as depriving her.
21. The mother simply regards the child as her property, and sees the father as making a claim on her ‘possessions’.
22. The mother dislikes the fathers new partner, who she sees as a rival ‘mother’, so prevents the child seeing the father.
23. The mother’s new partner is the one who is preventing contact because he wishes to be seen as the ‘daddy’.
24. She fears the children will leave her for him.
25. She wants to prove to her new partner that he is the only man in her life.
26. She may have come from a broken family, and not be able to sustain a relationship.
27. The father is a constant reminder of the failed relationship that she prefers to forget.
28. She may be starting a new involvement, or having difficulties with the existing one, and doesn’t want the children to tell the father about her affairs.