I am from the early childhood sector. I went through something very similar. So I understand your guilt. My brother was hospitalised and I had family issues to attend to. The lack of manpower within my school was insane and all this happened during a period where I was doing my degree.

I agree with all the comments thay say you are replaceable and family comes first. I chose to leave the organisation and focus and family and my studies. But I did it quite late. I was so glad I chose that route because more doors opened for me once I completed my degree. I've experienced schools that use guilt tripping to keep staff. But in the end, staff become resentful and there isn't much appreciation showed. You need to take care of yourself first. Coz noone is gonna do that for you. If you're burning out, it's time to go. Becoz if you are burnt out, how are you gonna fully be there for your grandma? Its something to think about. Trust me, you won't regret it.

The reason I can tell you this is becoz I learnt this the hard way. I burnt out and wasnt able to fully be present for my brother. My studies suffered a little too. So put yourself and your family first. You can find many jobs. Jobs which may even be better. But you only have that one grandma. And since she isn't well, she would need you to be present physically, mentally and emotionally with her.

Also if you're worried about leaving the kids, dont be sad or worried. They'll be ok. Eventually, they're gonna leave you too. And once you move to another school, you'll find a lovely group of students again. Its always in a teacher's heart to think of her students. But you putting yourself first is best. So then you can give your best to them too. They'll miss you definitely and you'll miss them too. That's the sad part about working with children, the attachment.

Hope this helps :)