The OP does have an income, rental income from her London flat which will pay the nee mortgage. She’s also doing all the childcare.
As others have said, OP wants to put her rental income straight into an asset (despite the fact no bank would ever accept that) while his earned income goes on food and energy and taxes and clothes - as it has been for the last decade. Hardly fair is it? When OPs tenants stop paying rent for 6 months is she going to default on the family home mortgage or expect DP to step up and contribute?
Yes OP is providing childcare but lets be real the children are 8 and 11, it would be significantly cheaper and in his own interests for the DP to pay 50% of the after school club (and even 50% of a cleaner) than continue to pay 100% of the entire families expenses AS WELL AS depriving himself of a stake in the home he's going to renovate, live in, and maintain. That is literally the worlds most expensive childcare when you take into account how much the house will appreciate over what could be twenty years and the work he's going to do to it.
Clearly he is not acting in his own interests though, he's acting in the best interests of the family as a whole.
Of course SAHP make a valuable contribution but I'm sick of hearing it magically equals the playing field financially, so what's his is theirs and what's hers is hers. It can't be worth the same amount of money as a partner who's a hairdresser AND a partner who's a consultant doctor, can it? A private nursery for triplets is going to cost more than an after school club for a single ten year old. Also sick of people acting like the SAHP is saving the WP the full amount that childcare, a cleaner etc would cost - no, they're saving the WP 50% of it.
But thankfully for most families it's not about that, it's about the family as a whole.
I can't believe anybody who is posting here would put themselves into the DPs position. No savings, no stake in the family home which can be sold at OPs say-so, the sole financial responsibility for an entire family, the risk of having to pay a mortgage on a home you don't own should OPs tenants stop paying rent, and having to hold down a full time professional job while a partner who has the full benefit of the appreciating asset sits at home with school aged children all week.
All for the benefit of saving 50% on an after school club which isn't even going to be necessary in a couple of years time. Anyone happy with that needs to get their heads looked at.