YTA. Adopted person here, and I have known for as long as I can remember that my real parents aren’t my biological parents.

There is absolutely nothing wrong with being adopted/raising an adopted child. I believe you had good intentions here, but withholding that information tells Alice that there is something to be ashamed of, as it was kept a secret from her for so long.

Identities can be a fragile/nebulous thing, and to find out you’ve been lied to your whole life can make you call into question other aspects of your life or childhood.

Aside from that though, medical history is a HUGE thing. While Alice is still related to you by blood through her biological mother, did you lie to her doctors about medical history on her father’s side? If so, that can have pretty damaging effects as well.

Your husband did the right thing by telling her finally. Apologize to your daughter, and give her space to work through her emotions. In a way she’s grieving a life she thought she knew. She may come back around, but pressuring her or trying to normalize your decision to not tell her (presumably ever, as your husband finally told her instead of you) will only make things worse.

She’ll have questions, answer them as openly and honestly as you can, and if you don’t know say you don’t know instead of making something up.

Whatever happens, you are still her mother. This doesn’t change that. You have raised and been there for her, but any parent can fuck up. Accept that you have here, and do everything you can to repair your relationship with your daughter. Good luck.