Xenia -
I don't do much cleaning for my partner, so that value = £0. But if I did it instead of the cleaners, it would be a miserable pittance
I do manage our household and lives though, pretty efficiently (he is hopeless at that on his own though quite good at making the right decisions if he is supported and he loves spending time with his children). By managing household, I mean children's upbringing, education, activities, our homes, holidays, cultural and social activities so value £ = pretty high (there aren't in fact so many of us on the market with the same experiences to bring to a relationship)
Investments - I bring a lot of value here on long term projects and investments
Work - he talks to me about work and I do solve some major problems for him (I have a professional network he doesn't have) so consulting services - £ = pretty high
Sex - I enjoy making love to him as much as he does to me so there is no monetary loss or gain to either party though there is of course a lot of value accrued to to both parties
And we have fun together, lots and lots of it = lots of value to both of us
I don't think a healthy relationship is ever:
Money versus housework, childcare and sex