Work Issue

So, for the first time ever, I made my first monumental mistake at work, and I don't exactly know how to deal with it. Most people can separate job life and home life, but for me they inner-twine. I can't leave work at work; I take it personal. I have been here close to 5 years, and it does mean something to me. So, I had to approve paperwork for a $47K order. It got submitted late because I was out of town for work. While out of town, we worked 7:30 - 6:00 every day, then had dinner, not returning until 10 every night. So, my regular work fell behind. I know that isn't an excuse, and I don't mean it to be, thats just how it was. By the time that I got back to the hotel every night, I was doing work for the next day's show and just couldn't get through anything else. So, it looks like the shipping center is going to be able to save my butt and get the order out on time, but I don't know how to avoid feeling personally responsible for almost blowing a $50K order. Mind you, we get them every day. But that's more than I make in a year. I keep mentally reprimanding myself, though I know that we all make mistakes. Just don't know quite how to deal with getting past it and keeping it from happening again.