Interesting thread!

I was young and perhaps niave when we married (him less so). I just felt I loved this person more than anyone ever and wanted to spend my whole life with him. Marriage itself wasn't necessary for that but on practical level for joint finances/pension rights etc it was. It made things simpler and more clear cut as parents too.

The term contract idea I have read about too and it sounds interesting. But can you imagine when the end of the lease approaches and the discussions/ negotiations? Lol.

Over all I think it is a societal concept to do with stability and care in older age particularly, some countries give tax benefits to those in marriage/civil partnership. It's encouragement to keep units together. Not very romantic but there you go.