What is the ruling on one who fulfills her emotional and sexual needs by lying on her stomach and making movements that arouse desires? Is this forbidden, and what is the solution?

What this woman is doing, whether masturbating by hand or rubbing against the bed, is a secret habit forbidden by Sharia, because it is among the aggressions mentioned in His Almighty's saying: "But whoever seeks beyond that, then those are the transgressors." [Al-Mu'minun: 7]. So, she must fear Allah and repent to Him.