The eminent Muslim scholar and renowned Da`iyah, Sheikh `Abdel Khaliq Hasan Ash-Shareef, states: As a wife, if there is no emission of semen on your part and there is no contact or touching between the genitals as you mentioned, then you are not required to perform Ghusl. In case the semen came out from you, then you are required to perform ghusl.”
To furthermore, masturbation between the man and his wife (the wife masturbates her husband and vice versa) is not Haram, rather, it is permissible, because it is a part of the enjoyment which Allah has allowed. Allah Almighty says: “Those who guard their chastity (i.e. private parts, from illegal sexual acts). Except from their wives or (the captives and slaves) that their right hands possess, – for them, they are free from blame.” (Al-Mu’minun: 5-6).