She is TWO. Daddy-worship is fairly standard during the toddler years. I remember someone telling me that my babies, when they were very small, would seem to look like one parent one day, the other the next. Because they’re just changing that fast. So they told me not to get comfortable thinking she is my mini-me. Because tomorrow she will be his.
It is the same with parental preferance. When babies are totally dependent, they naturally do the bulk of their bonding with Mom. Especially if she breastfeeds, but always. It’s nature. So, doesn’t it make sense that once they gain a little independence they would seek out a closer relationship with the breastless parent?
The other thing I have learned is that children tend to be more dismissive of the parent they feel most secure about. They know Mommy is not going anywhere, but they’re not yet sure of this daddy person. So they cling to him for awhile, seemingly all about Daddy, but once the child feels equally secure in their relationship with dad as with mom, and gains a bit more independence, the parent-child relationship for both parents tend to equalize, and BOOM, school starts and from Kindergarten until forever, their friends will be more important than you OR dad.
You are mom. Nothing can change that. Nothing can take it away or diminish it. You undoubtedly got used to being her everything at first, as we all do. But her world grows with every new person that becomes a part of it, and she gains more and more everything, and it has to be bigger than you. But you were numero uno. You are her entire history. She will never love anyone quite the way she loves you.