Part of my Alanon recovery is going to be making amends to my ex. There are many things for which I owe an apology. It's part of the program. Another part has been learning to forgive myself for my mistakes.
And there's no guarantee that you two would have been any happier or that your relationship would have worked out if you had found Alanon sooner. There are things that you might have handled better, sure, but Alanon is not a magic wand to fix a broken relationship.
It also sounds like drinking is her #1 priority in life, if she is losing relationships because of it and still not examining herself. Breakups hurt, but that doesn't mean they are all bad. You may have just dodged a bullet.