The Catechism is clear:
2352 Both the Magisterium of the Church, in the course of a constant tradition, and the moral sense of the faithful have been in no doubt and have firmly maintained that masturbation is an intrinsically and gravely disordered action.” “The deliberate use of the sexual faculty, for whatever reason, outside of marriage is essentially contrary to its purpose.” For here sexual pleasure is sought outside of “the sexual relationship which is demanded by the moral order and in which the total meaning of mutual self-giving and human procreation in the context of true love is achieved.
2396 Among the sins gravely contrary to chastity are masturbation, fornication, pornography, and homosexual practices.
If masturbation, like “homosexual acts”, contraception and cohabitation is indeed “gravely disordered”, why is the Church not talking about it? (It’s not as though nobody does it.)
As always, let’s begin by considering some simple facts, the reality behind the theology.