“You said that you encouraged someone to keep her head covering after she divorced, which would also be good for chinuch”
Just for the record, that lady was widowed, not divorced. Also, just for the record, I am not sure that there is even a reliable source for someone who was previously married to uncover her hair. Even though she told me that a Rav told her she doesn’t have to, I have no idea who this Rav was. There are a lot of Rabbbanim out there, and they are not all reliable.
In any case, I still would have told her what I told her, even if there really is a reliable source for uncovering one’s hair in such a case. But I don’t want you to have the impression that there really is a source for uncovering one’s hair if one is widowed or divorced. I do not know if there is or not.