Ann the best advice I can give you is to just let it go. Let it go and never speak of it again. Don't try calling him. Don't try tracking him down in the pub (not a good scene, promise). Just do try and breath, focus on tomorrow with Seb and rest as best you can. You've done the talk it out route. You've probably done the yell it out route. Now's the time to just leave it alone. Don't waste your precious energy worrying over it.
Ignore this if you like. I'm only saying it from the heart having been there with DH. We are still together if that helps you any.