How do I help my dog with stress?

My little American Eskimo was just fixed last Friday (June 12th). I took her and my Lab/Rottie mix at the same time. She was a bit high-strung since a few days before that because my other dog who was almost 14 was sick and I guess this stressed her out. We had to put the older one down the other day and I think this stressed my eskimo out even more. During the day she hides in the corner and doesn't want to be bothered. At night she comes out for an hour or so and then goes back to her corner. When she is out and about she gets very hyper. Like she's watching everyone and she runs around everyone making sure they're okay. I'm almost positive it's stress...probably from the combination of her not knowing where the other dog went and her getting fixed. It's starting to worry me a little and I was wondering if there were ways to help reduce her stress? Thanks!