I don't feel guilty about it. We all have those days, even people without mental health issues take days off because they just need a break. But taking a day off is almost more stressful than going to work for me. I'm a teacher, so I can't just call in. I still have to go up to school and set up lesson plans (often something completely different because a substitute can't usually do what I had planned). At that point, it's often just easier to go in and teach quite frankly.