Ok, first things first. We know that the apology likely killed him, LOL, but he did it and that says something. He should have been clearer with you about the time, saying he had to be leaving your house by 12:30pm or something along that line. It was just a bad bout of poor communicating. I am sorry it escalated a bit, but its really ok. Its like that pressure cooker that has to be released sometimes.
And yes, I do think your marriage has a chance. Think of it this way, you guys would have had a fight like this (ok, not the same subject LOL) while together, it just seems worse because of everything else going on.
Shake the exchange off. I feel bad for you though, talk about feeling attacked, and out of the blue, huh?