If you are an unregistered domestic partner and you do not have a written agreement, the situation is complicated but not impossible. You will need to prove that you contributed financially to the purchase and that there was an agreement to share the property. This demonstration requires proof: bank transfers, messages, emails where “our house” is mentioned, testimonies of family members, etc. You could claim judicially either the recognition of a community of property on the property, or the return of your financial contributions for unjust enrichment of your ex-partner. These procedures are complex and lengthy, so it is always preferable to regulate these situations from the beginning.