Thanks. Please hide your spoilers. I slept through much of the movie (I still liked it) and won't have a chance to watch it again for awhile.
You--lighten up. You--big trouble. You--get in the car.share
There's no one clear cut reason. Probably a combination of she didn't know if she could fully trust him (remember that scene where they were kind of arguing and he tries to reassure her that he supports her) and that she didn't want to endanger his life. Perhaps, also, she wanted at least one special thing in her life that wasn't tied to all of this madness. If he were involved, they would be talking about it constantly- having discussions, fights, etc. She probably didn't want her work to infect this relationship.
The British government was implicated, telling him would force him to make a choice between his country and employer, or his wife.
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