I'm so sorry your summer is so full of stress.
I know it sounds crazy, but exercise is a good stress reliever. But it sounds like you don't even have time in your day to exercise in addition to your full (+some) day of work.
Just keep your mind in focus, and it is if you are even posting about this. Once the new store opens and things settle down, you can get back into your routine and drop any pounds you gained over the summer. You've done it once, you can do it again!

Good luck to you and I hope it slows down for you SOON!!