I have the rare disease of sending embarrassing messages to my ex's after a couple of drinks

How come you never asked the doctor what was the condition of his "brain disease"? I think YDI.

Honestly my mum used to come up with all sorts of weird reasons for stuff she did/said and cos I don't really drink or hang out with people that do it took me a long time to realise she was bullshitting and shes just a drunk. Sorry dude. I remember reading someone that when someone has an addiction that they go through denial, but the people around them have to too when they realise and that's why it takes people a long time to come to terms with it sometimes. Maybe. Anyway, don't beat yourself up about it OP.

You must be really young or naive. Or in a lot of denial. Now that you know, it's going to take a lot to process. If it gets too hard, don't be afraid to seek counseling. Trust issues might crop up for you if you brush it under the rug or act like you're not upset in any way.

There wasn't a time that you realized that his symptoms were very similar to the "symptoms" of being drunk? That being said I can't vote YDI, because I can't blame OP for trusting their father when he says that he is sick. The dad is a dick for taking advantage.

Everyone gather around and let's give OPs Dad prankster of the year award and OP the dunce of the year award.

At least you care enough to take care of him, even if he doesnt have a disease

My father in law quit drinking after 30 years; he's currently living in my basement to get back on his feet. He has what I call stupid **** post drunk syndrome. I know he's not drunk because it's obvious when he is but he kept 30 years of drunk habits. I can look this man in the eyes, tell him something, he will nod then ignore what I said. It's not selective it's everything either of us say to him. It's been a couple of months and I can't get him to even wash his own god damn dishes or clean up after himself in the slightest. It's possible your dad did cause his own stupid **** post drunk syndrome. If not sorry you've wasted so much time tending to a drunk OP.

Having a father who is an alcoholic, I find this hard to believe. At a minimum you would know he is drunk, alcoholics stink like booze all the time.

Chemical dependency to self treat what is likely depression probably counts as a brain disease.