Be concrete for once, instead of scattering ethereal platitudes about paying for music.
Exactly who is allowed to do what and what not in a relationship to your liking, if, let’s say, only one partner works and the other takes care of the children? Who should be grateful to whom here?
And what exactly do you mean by gratitude? Reminds me of the many stories where the abandoned rich guy complains afterward that he gave everything to the relationship (and means money, because he has no clue about the more essential rest).
Possibly you are also using the term "gratitude" carelessly. Do you mean "mutual appreciation"? But that is something entirely different!
Gratitude is something I show to people who have helped me with an act that is not taken for granted. But in a relationship, many things are taken for granted and thus gratitude is not appropriate – on the other hand, there is appreciation. The more self-evident the mutual support is, the less gratitude is appropriate and it should be replaced by appreciation.
And if you work with the angle of "gratitude," it has a whiff of performance and counterperformance, know your place. And all that even "as a prerequisite"?? Seriously?
Maybe you mean that quite differently.