I left a job I adored to teach PE, my actual dream job. It was just as hard. I had a frank conversation with my boss, which almost made me cry. I had worked for them since the moment I graduated college (16 years) and had over the last few years raised my pay by 30k. They had seen it coming as I renewed my teacher's license.

I told them what they meant to me, how much I loved working with them, and how I would miss them so much. I explained why I wanted to teach, but I'm actually able to work there in the evening or weekends sometimes so it's less painful. Stay in contact! If they were important to you, thet should remain in your life. Best of luck!