Lara & Harry: There seems to be a problem ...

I was skimming Blood Rites due to another post, and I see this:

“The White Court can’t touch someone who is in love,” I said. “Real love. If they try to feed on them, it causes them physical agony. It’s . . . their holy water, I guess you could say. Their silver bullet. They’re terrified of it.”

There's nothing in that sentence that indicates that marriage has any effect on this.

Can anyone add clarification?