Hi and welcome to SR. None of this is your fault. You didn't know about addiction. A lot of people think they know about addiction but the reality is that most addicts can't quit cold turkey or can't quit at all. I was once in a similar position. I asked the addict in my life to quit and to go rehab. He said he could quit cold turkey because rehab was like joining a cult. Well, he never quit. Every time he tried, he was extremely sick. Please don't blame yourself for the things you didn't know. I don't even think you were irresponsible for what you asked him to do, because his addiction was never your responsibility in the first place. Asking to be in a relationship with someone who is not an addict is completely reasonable.
That said, he is an addict. And you should be asking for a sober partner. Therefore, you can't be asking him to be your partner. He's got a long, difficult, dangerous journey to walk. He may quit and relapse many times before it sticks. He may never completely stop. He may replace the alcohol with another type of addiction. I suggest you take some time for yourself and not worry about him for a while. Trust him to God (or the universe... or whatever higher power you believe in). Seek help from Alanon and maybe things will get clearer. SR is a good place too. I hope my response was helpful in some way.
There's a saying around here that helps: Let go and let God.