Answers like the one above do more to drive people away from God’s love, mercy and forgiveness and right into despair. Masturbation can be, but is not always a mortal sin. There are complicated issues both physical, mental and moral that must be considered in evaluating one’s degree of responsibility. A good priest can make that determination… not us!
Suppose a marine and his squad who are out of ammunition are hiding in darkness awaiting the heavily armed enemy to pass by on a dirt road in the dark of night. One sneeze will result in the entire squad being discovered and their capture or death. Now imagine being a young marine with the beginnings of a cold. Of couse it’s possible to hold back a sneeze, but sometimes no matter how hard you try, it’s coming out.
How about an itch? If someone offered you five hundred dollars not to scratch any itches and hold back all sneezes for one week, could you do it? Certainly, masturbation is more a serious issue than an itch or a sneeze, but the physical principle within the body is VERY similar. Scratching itches and sneezing both provide relief and are pleasurable to the body by the way!
Here’s another question: Suppose an generous, responsible 18 year-old boy who attends daily Mass, regular confession and is saving himself for marriage, finds a dirty magazine in a restroom and is overpowered by temptation and winds up masturbating. He fully intends to confess his sin when he goes to confession. While driving to help his sick grandmother is killed in an automobile accident. Did this sin cause him to go straight to Hell?
Before you accuse me of making excuses for masturbation, understand this: The catechism says that masturbation is an “intrinsically and gravely disordered action”. Nowhere does it say that it is always a mortal sin. Masturbation is an extremely primative and most natural act that occurs in many of God’s creatures. The forces that drive it in mankind can be very complex. As people of God, we are called to a higher standard of behavior than mere animals. People who struggle with this need to consult with their priest confessor regarding their level of accountability.
Her goal should be to focus her energies on getting established in her state of life, attend regular confession, include daily prayer as a priority and yes, DO HER BEST to refrain from all sexual activity until it can be expressed in an appropriate loving way in the marriage bed as their God given intended purpose.