Henry isn't Nan's boyfriend; Pablo is.
Think about it for a moment.- Pablo has been with Nan for a longer time.
- Pablo has made himself much more useful than Henry.
- With the reveal that Henry is the Pilgrim, who knows....
Otherwise....
Nan doesn't have a boyfriend at all.
We've seen her as a nun in flashbacks. This may mean she doesn't have a partner at all.- However the case could easily be that her boyfriend was a secret, or maybe her church just didn't mind.
Nan is Henry's wife.
From this post.
We've seen the hotel remove memories, but we haven't actually seen it add fake ones. Nan has two mutually-exclusive backstory memories: one where she's single and one where she's in a relationship with Henry. But if the hotel can only remove things...what if the memory without Henry was the fake one? It would also be cruelly ironic to make Henry kill his very justification for killing people, which seems like something the hotel would do.