I think its a common feeling. It is for me sometimes. Doing the same old stuff day in day out, stuff like making beds, washing, cleaning, meals, organizing everyone & everything & because you do it all the time it is taken for granted, along with you....so I get how you feel.
You need to take time out for you. Have an interest or hobby.
Set chores/tasks for the family to do..DH included, may not be easy but if they want things then they will have to work for it.
Put your foot down & be selfish.
I am not surprised you feel this way as you had your first child when you were very young & have had kids around for 20yrs...time to take back a little for yourself