That just sounds like a refinement of “you’re responsible for your own happiness”, which is a maxim of selfish people abusing therapy talk to justify their apathy/callousness towards their partners.
Partnerships are collaborative efforts for mutual gain, not zero-sum games where we’re individually responsible for maximising our own output from the system. A good partner should actively want to see their partner happy and fulfilled.
Sounds like we have the same reading of that statement, and I would say a very similar reading applies to “you’re responsible for getting yourself off.” My issue is with people misappropriating the message to assert that it’s somehow okay to be apathetic to your partner’s needs.