I was with my last Little for 10 years, and I can honestly say, when you create a true DDlg love, it never goes away , We've been split up for about a year, and she still calls me daddy, still texts me whenever she is sick, sad, lost, lonely, depressed. And I never reprimand her for still reaching out to her "Papa", because I still feel like it is my duty to be there for her always. BTW, Her boyfriend has no idea. And she doesn't call any other BF "Daddy". Actually, we had established that I was not her Boyfriend. I was her Daddy. When we tried having a regular Boyfriend/Girlfriend type of relationship, it would always fall apart. When we started researching DDlg, it all clicked into place.
If you want to be a good loving DD, you have to love unconditionally, and that can be quite difficult at times. I would always tell my ex "If you find a man that makes you happier than I do, go with him." And, even though she did find that man, she does NOT call him Daddy. The emotional bonds you create are very strong, and you'll know when it's real.
Your Little, even if she leaves you, will turn around as she is walking away, reach out her hand and cry out "Papaaa" So if your Little just walked away and never looked back so easily, she was never your Little to begin with. It's ok, though. Your loving Baby Girl is out there waiting for you to find her.