School drop off guilt

When does the guilt of dropping off the kids at school go away? My girl is in 1st grade and I find myself in tears after driving away from school drop off quite often. I have a 2nd child who just turned 1 and I am expecting my 3rd. When does this guilty feeling go away? Even when I wasnt yet expecting sometimes I would full on sob after dropping her off for school. Her school is amazing, the teachers are lovely, shes made friends, why do I feel so guilty? If we had our own home I would probably homeschool. I just dont see how parents do this and feel okay. Anyways thats my vent for the day.