I know it's hard...
Being a teacher is probably one of the most demanding jobs that exists in terms of the commitment, passion, and dedication that it requires. In some jobs, you put your time in, go home and relax, and forget about the challenges of the day, that customer that complained, that client who was unhappy, or possibly that project you're working on in the office.
Teaching is different. As a teacher, you invest so much in your students emotionally, financially, and professionally, that its hard to let go just because a bell rings at the end of the day. Whether its a student who told you about their troubled home life, didn't grasp a concept, or got embarrassedin front of their friends...those moments stick with you.
There is absolutely NOTHING that is going to change this aspect of our job. If you aren't invested in your students, you're probably doing it wrong.
However, if you are constantly focused on your job as an educator it can start to wear on you. It can even start to negatively impact your personal life, your relationships, and yes...as weird as it sounds...your performance as a teacher. Being too consumed by your job can actually hurt your ability to perform that job to the best of your ability.
If this sounds like you, don't worry! There are some things you can control to make it easier on yourself. Many teachers I talk with are always worried about planning, grading, that meeting they have the next day, or that observation they have coming up (which by the way you shouldn't stress out about...seriously)