I agree there wasn't any fighting Kas, people just didn't know the whole story before.
All anyone can do is their best and this is what you have done. You have done your very best.
Your energies now can go into finding the best situation for her.
I think we have all had to hearbreakingly break promises due to no fault of our own as circumstances can change as we can not control that no matter how much we wish we could. It is one of the hard lessons we have to learn and to try and accept it is not our fault.
If we can't change the situation we have to change how we cope and deal with it..in this case it is now trying to do the best you can for her future, whatever that turns out to be.
She will always carry you in her heart and know how much you tried.
Sending you lots of hugs.