Let's keep it simple. A marriage should involve one noble being able to marry another noble. Either party should also be able to dissolve the marriage if they wish.
So if your roleplay is that you're married for life, til death do us part, and the only real marriage is between a man and a woman then that's fine. You can marry another noble of the opposite sex and you can never dissolve the marriage. On the other hand, if your roleplay is that divorce is fine, you can marry as many people at once at you want and it doesn't matter what sex they are then the marriage mechanic should accommodate that too.
Game mechanics should enable, not dictate, what players do with their characters.
In terms of what happens if your spouse gets paused, deleted, etc. I think it should follow a simple rule that a dead or deleted character is treated by the game as being dead in terms of the marriage - if the other player agrees then your deleted spouse can become your NPC but otherwise you just RP them as having died. A character who is paused is just that, paused, and unless you're given permission by the player of the paused character then any RPs involving your spouse should be limited to them being in a coma, or suffering from sleeping sickness, or similar.
