This was a few years ago. But I put in my 1 month as a courtesy and my manager said at the time “you know you are really leaving us in the lurch” I just professionally said yup the timing isn't great for Company X but it is the right move for me and my family.
Now I'm with a company that values my opinion and is often finding ways to make employee engagement meaningful. The more I look back at the old job the more I see it as a formerly abusive relationship where boasting year over year record profits but not giving out raises – even based on individual performance. I was top 3 sales for years and was still paid less than some more senior members who were phoning it in.
I just don't understand how we got to this point where success is because of the managers and failure is hoisted on the employees.