Community of accrued gains in construction

I have been reading along here for a while, and although the topic is already older, I specifically registered (finally) to write something about it.

I fell exactly into the trap described. And I thought I had been paying good attention... My now ex lived with his wife and child in the inherited house, he separated and moved out. Then our relationship began, we initially lived together in a rented apartment. Then his ex-wife moved in with her new husband, the house became empty. He took out a loan, it was extended and renovated, and then we moved in. I consciously did not participate in the construction costs, but initially continued to pay my half of the rent, now to him. Our money was always separate, I said that neither his house nor the child support for his child concerned me financially, just as his horse did not concern him. Otherwise, we always balanced things of common need (shopping, vacation) equally.

Then the children came, along with my part-time job. I then stopped paying for housing (after all, I gave up income). He always put all the money into paying off his loan, was practically always "broke" (so life was possible, but there was never anything left over). When, for example, a proper kitchen was needed, he could not contribute. When the family car was stolen, a new one was supposed to be bought by us (but from my money), certainly in his name... I refused and bought the car myself.

So I thought I had kept an eye on not getting financially involved in his house... but when the relationship ended, I saw: I had saved several thousand euros, he had nearly completely paid off his loan and thereby, as well as through the increase in the property's value, easily doubled his assets from previously 250k€. Nevertheless, I was called a parasite, after all I had supposedly not contributed to the housing (my objection that I had given up 800€ per month to take care of the children was dismissed). He was supposedly penniless (maybe in cash), while I had saved fat... so the views of the situation were very different.

By the way, I moved out, we now share childcare equally, but it would never have been an option for me to stay in HIS house...

Well, that is history now, I am standing on my own feet again, have bought my own house, and let the past be past...

Thank you for the brief but precise insight into a situation that one is reluctant to anticipate, often belittled by the stupidity of others, yet can happen quickly.

It remains to be noted:

2 partners, no marriage
House construction. One of the partners is registered in the land register. (weakest constellation, a losing hand for the partner without land register entry in case of emergency)

At this point, it would be fairest to conclude a partnership contract that regulates the claims/obligations of the partner without land register entry. In my view, both activities (one partner stays at home to raise the children / the other works) are equivalent, so the joint increase in assets should also be regarded as equivalent. Nevertheless, this type of contract is rather rare. Unfortunately! With the consequences described above.

2 partners, marriage, classic community of accrued gains (solid legal framework)
One of the partners is registered in the land register.

The spouse without land register entry is entitled to at least the accrued gains.
However, there are of course certain tricks to minimize one’s own assets.
Expensive furniture and such items do not count as assets.
Or one partner takes out a loan just before for the construction of a pool...
Overall, though, a solid arrangement.

2 partners, marriage, marriage contract
Theoretically, of course, the ideal case to clarify the above problems precisely in advance.

Ultimately, I simply did not benefit from the wealth accumulation that was (also) enabled by my part-time work and “management” of the house, garden, and children, while he was able to pursue his career.

It would be foolish to put any more personal funds directly into the house, for example for special repayments. Or a joint account, joint money, and all surpluses going into his house. Such ideas were brought up as well, but I did not go along with them.

However, he brought the house into the relationship, so it was not acquired during our time together.

Well, I would be ashamed to throw my wife and child out of the shared house just because they are not listed in the land register. Here, if anyone leaves, it’s the man.

Another liberal again :-p, then you can play cards in your living room in the evening with the new guy who is screwing your (ex-)wife.

We are both listed in the land register and neither can pay out the other in any way due to the construction cost.

In case of separation, the only option remains the sale.

My husband is listed in the land register
However, not because he earns more
There is a prenuptial agreement for the divorce
If we grow old and gray together, in the end it doesn't matter