Good it seems that this thread has not been very popular, in any case I leave the only option I have found to solve this.
1. Download and install
Developer Console as indicated in nexus
2. Run Mount & Blade II from Steam and in the launcher go to the Mods section to activate the Developer Console, start the game.
3. Load a save game in which we want to marry, once inside the game open the console by pressing the ctrl + ~ or ctrl + º keys.
4. In the console type "config.cheat_mode 1" and then "campaign.marry_player_with_hero liena" if you intend to marry Ira, type "ira" instead of "liena" or if you want to marry Phaea, type "phaea" instead.
5. We will be notified that our character has married, so we type in console "config.cheat_mode 0" and save the game.
6. We exit the game and if you want to delete the mod you can go to where you installed it and delete its folder, we start in Mount & Blade II launcher and deselect the activation of the Developer Console, start the game and load the save game.
To consider:
Once we load the game we will see that the skills learned from our wife seem disabled, this was solved for me by having her party dissolved and asking her to join mine. Consider that once your wife's party is removed she will appear the next day in the settlement that is considered your home and only there can you ask her to join your party.