Saintprudence unfortunately for me, the Catholic rulebook — canon law, that is, not the Bible — is extremely clear on masturbation, and I read the rule book and believed it when I was young. Masturbation is still officially considered to be a “gravely disordered” mortal sin by the church. They don’t emphasize it as much, but it’s there.
I understand where you're coming from. But the Catholic rulebook was written by mortal men, not by God. And why should we be bound by what some group of mortal men said, even St. Paul? This is why I said above I try to think about what Jesus would have thought said and done and act accordingly.
So why should the church say masturbation is bad? So MEN can get women to marry and have sex with them. The MEN who ran and run the church wanted women to think the only valid way to have sex is to marry a man. Thus men would have a reliable and exclusive supply of women and sex. If women can masturbate and have sex out of wedlock why do they need to marry men? I DO plan to marry but I do not want to have to marry some guy so I can get myself laid.