Lawline svarar
Dear sir,
*Legal regulation*
According to present swedish law, two persons who are living together under circumstances which are similar to those who applies in a marriage, are considered to be "sambor". When deciding if the sambo-relationship has lasted long enough in order to be labeled samboäktenskap, the legislators opinion is that a guideline could be if the relationship in question has continued in 6 months. It is to be noted, though, that a overall assessment has to be done, meaning that other factors also could be considered.
According to sambolagen, which is the law which applies on sambo-relationships in Sweden, all property the sambos have bought to the their common home is regarded as sambo property. This includes an appartment if it was bought in order to serve as the sambos common home during the relationship.
15 § sambolagen states that, if the equal division of the sambo property would lead to excessive/unfair result, it is possible to adjust the division of property in order to acheive a more reasonable result. If one part in the relationship has contributed with a significantly greater amount the 15 § could apply.
*Summary and advice*
Lastly, my opinion is that you by using 15 § sambolagen could have a chance to prevent your ex from getting half of the value of the house.
Best regards,