I do want to move on - it's the closure part I'm struggling with. But also what you just said there, what happens if he does end up being successful and say 3-4 years later he does reach out to me and truly is sorry for what he did. I know it's a long shot he'll be successful and a long ways off, but I've always been the type of person who thinks so far ahead. Trying to process everything right now and that's something on my mind. Is that something I'd be able to forgive him for now that's he's in a normal state of mind.
What if, in 3-4 years, you have met someone with whom you are truly happy? What if you are married to someone who truly loves and appreciates you? What if you are happier than you have ever been in your life? What about that? Are you planning to put your life on hold and stand around waiting to see if he is successful in recovery and tries to contact you? Of course you aren't, at least, I certainly hope you aren't.
Unfortunately, what he has done is not uncommon. If you read around the forums here, you will see that it happens quite often. It's an awful thing to have happen to you, but you will survive. Whether or not he gets sober and tries to apologize is anyone's guess, but it rarely happens. So, grieve the loss of what you hoped for, but don't let it stop you from moving forward and finding your own happiness.