Sell the house or keep it alone in case of a theoretical divorce?

You have already received the most important information here. If a separation should actually occur, the first thing I would do is free myself from the need to absolutely keep the house. I have experienced it myself and I am currently seeing in my environment that many other things are neglected because of "keeping the house." Such a house can become a burden both financially and emotionally, which paralyzes the new; another woman might not want to move in there or might not feel comfortable, etc. I myself wanted to keep the house, but then I sold it and eventually started something completely new and free again, without such visible financial and emotional baggage. It is much more worthwhile to invest energy in the still existing relationship to be sure that you have really tried everything yourself.

Hello everyone,
maybe a short update on the topic in between: The whole thing is now more than urgent. Officially, we are not separated yet, but we have prescribed ourselves a "break" with separate bedrooms, everyone does their own thing, etc.

The reason is simple: I found out two weeks ago that she is having an affair with a fellow patient whom she knows from therapy. She herself is no longer sure about her feelings; as of now, according to her, separation is not an option either. Contact with the affair is supposed to remain, according to her, because it helps her a lot with the illness.

I don't want to throw in the towel just yet, but the overall situation is very stressful right now and separation is definitely on the table.

I have informed myself and would currently estimate the house at a realistic sales value of €650,000 to €700,000. Actually, from my point of view, there are only two real options:

1. Joint sale: I think the way forward is clear
2. She buys me out (which is financially feasible for her) and I have a clear cut for myself and can start "fresh" again.

That would mean from my point of view:

€675,000 sales proceeds or value
- €336,000 bank
- €100,000 loan from parents-in-law
= €239,000 "proceeds" minus incidental costs

€119,500 payout amount to me if we choose option 2.

Her parents have also taken over bills worth about €30,000 in total in parallel. We would probably have to deduct those here as well, if I see that correctly, right?

Are there any other "additional" items I need to consider, or do I have a mistake in my thinking here?

Your parents have also simultaneously taken over invoices worth approximately €30,000 in total. We would probably have to deduct these here as well, if I see that correctly, right?

These are gifts. But to whom? To both of you together or just to your wife? Basically, many other items are possible, but after one year of marriage, they will probably be rather manageable.

From my point of view, that would mean: €675,000 sales proceeds or value - €336,000 bank - €100,000 loan from parents-in-law = €239,000 "proceeds" minus incidental costs €119,500 payout amount to me if we take option 2.

How was the issue of equity capital with the construction? The house will not suddenly be worth a quarter of a million more since moving in a year ago. Definitely get legal advice before you make a wrong step – even if it costs something.

These are gifts. But to whom? To both of you together or just your wife?

Basically, many other items are possible, but after one year of marriage, they will probably be manageable.

How was the equity capital issue with the construction? The house won't suddenly be worth a quarter of a million more since you moved in a year ago.

Make sure to get legal advice - even if it costs something - before you make a wrong step.

We paid a total of €600,000.

Broken down:

€180,000 land
€400,000 house construction
€20,000 exterior facilities

Minus loan amounts:
€436,000
"gifts for invoice payments": €30,000
= €466,000

-> €134,000 total equity capital (split 50/50)
€67,000 per person

Regarding other items: We have now been married for 1 year officially and have a marriage contract that excludes inheritance matters from the accrual on both sides.

If your wife's lawyer is not a wimp, he will have the house appraised by a court-appointed expert. It definitely won't come out at 600k. The result will blow you away. If you can settle financially without a lawyer, do it.

The sale would then be an occasion for both parties to get the maximum price out of the house.