Of course she is selfish, that is the nature of addiction.
OP in your vulnerable state, you have unfortunately enabled her and caused yourself a load of grief.
She would of been offered a resettlement package, on finding out that she would be fit for discharge.
She hasn't wanted to go where she was offered, probably because she couldn't drink and have screaming matches etc with people.
Also, being in a hiatal means that she would be observed by professionals, still, which many don't want.
So they find "friends" to stay with, or go onto the streets.
If she contacts her SW/CPN, she will be found accommodation, she won't want this, but it is in her interests.
OP as good as your intentions are, you haven't done anyone any favours, here.