Oh poor little Maggie! Honestly Sam, Simon would do that as well because he was not used to me leaving and he still (a year later) hides when I put my watch on because he knows that means I'm leaving! Does Maggie have run of your apartment? Maybe confining her to a smaller space would make her feel more secure and comfortable. Also maybe try practicing leaving, go through the motions and leave for a few minutes at a time increasing it each time. I did this with Hallie just so she would know I was coming back. Do you leave the tv or radio on for her? Or give her a kong filled with peanut butter to keep her busy? Just ideas!
Simon said to tell Maggie she can come over and stay with him when you are gone and they can snuggle together