Not necessarily. For separation anxiety, what’s more important is that you establish comfort with your absol during her waking hours. Leave her in a comfortable atmosphere with plenty of food, water, and toys, and always tell her when you’re coming back. Furthermore, stick to your schedule, including when you’re at home. If you feed her, walk her, and perform all the same tasks at the exact same time, you’ll train her to understand the concept of time itself, which will help her know when to expect you. Then, reinforce this concept by leaving at the exact same time every day and trying to come home, also at the exact same time.
In addition to this, never leave her sight without giving her that cue. When leaving a room, tell her where you’re going, and when you reenter a room, announce yourself. This will train her to understand cues as well. Reinforce this idea by feeding her a treat every time she takes your absence well.
Once you establish these ideas, be sure to announce when you leave for work shortly before walking out the door, and announce yourself when you come home. Give your absol a treat if you come home to find your home in order and your absol fairly relaxed. Eventually, through a combination of strict schedules, verbal cues, and positive reinforcement, your absol will get a sense for how long you’ll be gone and when to expect you, so it will be easier for her to understand that you are coming back. Once that happens, you should find that she’ll be more and more at ease while you’re gone. She may even find it easier to sleep at night once she no longer needs to be constantly reassured of your presence.
Best of luck, anonymous!