Hello Desp and welcome to SR.
I'm glad you've gotten a lot of useful information from this site. It's the best one going and we're always here to support, hug and love ya.
Ultimatums usually don't work. One of the reasons is that they may be able to quit for the required time period, but then they usually go back. I did this to my husband, probably 5 maybe 6 hundred times. Kidding. Anyway, it always backfired on me. I got blasted by him for putting pressure on him because, blah, blah, blah, blah...and it always wound up my fault.
We all love our alcoholics. My husband is recovering...occasional dry drunk and my son has 10 months of sobriety. I love them both dearly, but that doesn't mean I like them all the time.
One of the best things you can do for yourself is start attending alanon meetings. Pick up all the free literature and read, read, read and read some more. There's a lot to be learned about the disease. And there's a lot of stuff you can learn on how to quit enabling and all the other stuff we do for our alcoholics. There's an amazing book out called "Courage to Change". I got mine at alanon for 10 bucks. But there's plenty of books at the library you can get.
Take care of yourself. Mentally, physically and spiritually.
Blessings