is lower than yours.
Itemize your duties (technical and administrative.) Draw up a list. Show the list to her. Point out the administrative ones to see if she agrees with (or minimize them to her liking.)
Set a standard for yourself and strive for that standard, rather than seeking her approval on every small thing. She is not going to give you that approval because getting the work done is not her priority, but securing her power is. If it takes her to belittle you and favor others in order to create that toxic environment to distract attention from her less-than-stallar capability, she will not hesitate.
Many bosses have narcissistic personality traits. Look up the term "NPD" and study this topic may prove beneficial for your ability to deal with it.
Stop feeling dependent on anything. Otherwise, you are a easy victim of manipulation.