You may be tempted to sneak out and avoid a scene, but that only tends to make your child more anxious. You can ease separations that are painful for both of you by establishing a consistent way to say goodbye, much as you might have already done to ease the stress of bedtime. The repetition of a goodbye routine will help your child develop a sense of security, and facilitate a smoother transition from your presence to your absence and back again.
The consistency and predictability will actually train her brain to anticipate your return.