I am in the U.S. I have both a Bachelor's degree in Nursing and Master's degree in Nursing, and experience as both a registered nurse and nurse practitioner. My most recent work experience has been as a Nurse Practitioner, receiving the higher pay commensurate with that degree and certification. Now I desire to work part-time and am willing to work in either area, which means I would be negotiable on my salary. Job applications, however, often ask what my last salaries were, and when employers see them, they immediately rule me out as a candidate despite me sending a cover letter. I found this out only by contacting potential employers, who were still reluctant to consider me after my explanation of being willing to accept a lower salary. I can only assume they are concerned I will leave them sooner or later for a higher salary.
First of all, are there any good ways I can let prospective employers know that I am not interested in the higher pay (at this stage in my lifetime) without getting into lengthy details about my life (single mom of teenager, taking care of older mom, etc.), and second, reassuring them that I am not going to jump ship when something better comes along?