why cant i get enough?

ok so my husband usually always beyond satisfies me. give me multiple orgasms and yet after we are done and he falls asleep I have to fight the urge to finger myself. I mean he usually spend a good while on forplay bangs me 10 minutes or so and then fingers me until I'm spent and beg him to stop. Why do I still feel the need play with my clit? when he is rough with me and makes it hurt in the best way possible I don't feel the need.