Paying "rent" to the partner... how?

He saves, you pay. I find that unfair

He repays, he pays interest, he bears the risk, and she lives there with him. Unfair? I consider the idea that he could be building wealth completely irrelevant in this discussion. No one is stopping the OP from building wealth as well. It is a win-win situation for both, so where is the drama?

Well, provided that the tenant pays some kind of rent that exceeds the interest (excluding additional costs, etc.), they help the owner build equity. Yes, that is how a rental relationship works. But in this situation, I find that as a basis for living together unfair. The money that she then puts into his repayment could otherwise be saved by herself. So not only does he benefit, she also loses. Sure, she also lives there. And probably cheaper than in an apartment. But in an apartment, she can do what she wants and has fixed rights and obligations. In this situation, I fear, rather not.

I still don't understand why it is unthinkable that half the rent of an apartment, which the couple could agree on, goes to the partner with the house. If the two actually rent something, these costs will also be incurred. It doesn't matter; in the case of renting, you just pay off the house to a stranger.

In the end, you still live better than in an apartment. So it's a gain for her too.

What I would never do: lump sum together in such a case, and put everything that remains into the house. Then she would really be paying off his place.

Because in this case he alone had the decision to buy. Either she goes along with it or not. I personally find that alone at least questionable, but it was not the content of the question. The question was what we other users think about it. Opinions differ.

I still don't understand why it is unthinkable that half the rent of an apartment, which the couple could agree on, goes to the partner with the house.

Because the rent goes to a third party. Both tenants "lose" money. If the TE pays him rent, she gives him more money than the cold rent. Cold rent in ownership is merely the interest rate; the repayment has nothing to do with it. So fairly share the interest (and of course also the additional costs).

I used to really want to be in the land register. I thought that way I would have more chances to have a good retirement provision and "make money" and not to forget: I wanted to have a say in the house.

Nowadays I think (one of my friends is like this): living in the big house, whose problems are always his to deal with... also has its charm....
For them it’s like this: the owner pressure-washes the yard, my friend helps with the household but working on the house; not her house not her "problem."

What I want to say is: there is no one right way, you have to find something that works for both of you...

If you don’t want any property at all, so what...
You can change your place of residence, partner, etc. anytime... he can’t or it’s harder for him...

If you stay together forever you can reconsider that... then you should look to buy a small apartment and rent it out... you could always move into it if you should break up...