OK, people make mistakes. Give you, and him, credit for both TRYING right now.
It's all going to work out OK. Don't need to beat either one of you up. Let it go, water under the bridge. Nobody meant for anything bad to happen. He's taking care of it now, he didn't drink over it.
I totally "get" that feeling that some disaster will "make" you drink. It's how you feel when you are first sober--you aren't used to responding any other way than panicking, getting angry, and drinking those feelings away. On my fourth day sober I had a sewer back up into my basement, COMPLETELY flooding it. I was freaking out, and at 10:30 at night my neighbor who had been slogging through the sewage with me trying to figure out where the water was coming from showed up at my front door with a cold beer, figuring I "could use this." Believe me, there was a long pause before I thanked her and said, no, I'm just going to bed.
It's learning to deal with these crappy little life problems sober that is tough in the beginning. I'll tell you, though, after that incident my confidence that it WOULD be possible to stay sober went WAY up.
You did the best you could, at the time, and he's doing the best he can, right now, it sounds like. No, he shouldn't have blamed you, but we don't get all better all at once. Sounds like he is trying to put things in perspective.
Hugs,