Even in the frosty land of Solstheim you will find some place for love. There are three characters who you can marry after meeting certain requirements. They are:

In order to propose, you have to speak with the priest of Mara – Maramal – and buy an Amulet of Mara from him. He can be found in the temple in Riften or at The Bee and Barb. After buying the item, put it one and speak with the person you want to marry.