it only became clear further on in the thread that she may still be drinking
It was clear to me the moment I read the opening post. All I needed was the word alcoholic teamed with If your father left you to die. This is all I need to switch off to every single other thing that the OP said. Everything will be a lie. Not a deliberate, malicious lie, but definitely not a reliable witness.
Drama = drinking = its not a true reflection of facts
All this debate about the correctness of the OPs words - is the brother enabling, is the brother talking rubbish, is the father mean, is the father doing the right thing. Is the OP homeless?
My 6 year old sometimes comes home from school and tells me Messi came to school and played football with them, and he got to wear the Ronaldo shirt and he scored a penalty against Messi. And Mrs Teacher was the referee and gave Luis Suárez a red card! And....
I don't say to my 6 year old "What your saying is preposterous, you are lying. Why are you lying?". I just smile and nod and say "that's nice" and move on.
I've not paid any attention to any of the OPs words. Because she's drunk so the words she says don't matter. That doesn't mean the OP and her feeling don't matter. But her words and feeling when she is drunk don't matter because they are not a true reflection of the facts.
There is just no benefit in becoming emotionally involved (or involved at all) with an alcoholic when drinking. Just smile, nod, ignore and signpost all the help there for them when they decide to sober up.
So I am not really understanding why negativity is being created in relation to differing opinions regarding the OPs father. OP hasn't even mentioned a daughter she (apparently) has. What makes anyone think she has a father at all? I don't take her imaginative thoughts as fact, so wouldn't get het-up about the details.