this was my daughter but to a much lesser extent, she always wanted mommy and there were a few things we tried that seemed to help. If she said she needed mommy I would say that “daddy is just as capable of helping as mommy is and mommy is busy so if you need help I am your only option, what can I do for you hun?” if she was throwing a fit I would hug her and soothingly say “its ok hun, daddy is here to help, daddy loves you and wants to help, what can I do?” and I would hold her till she settled down. I also said how it hurt my feelings when she did something like that in a plain honest way. I would set examples such as “if I were sad and she tried to comfort me and I said go away I want mommy how would it make her feel?” the important part is to keep calm but be firm and make sure your wife is on board and sends her to you if she runs away. Best of luck because it is an aweful feeling.