There are always chores to do around the farm. It seems obvious but somehow she never realised that her routine would become something that she's done for twenty years. Marrying Jonathan was as much a commitment to this life as a commitment to the man.
She loves living and working on their farm but she'll never let the simplicity of small town life lull her into forgetting that Smallville isn't the whole world. Jonathan and Clark both fit in here, where it's easy to choose to do the right thing.
She loves them dearly, but neither of them live in the real world. Jonathan believes in his platitudes about how things should be, and Clark is only just learning to see what the real world is like.
He's fifteen, and starting to look around him more closely. He still listens to her, still loves her with unbounded childish enthusiasm, but she can see how that's going to change. She can see the cracks appearing between Clark and his father.
Martha's always been keenly aware of the distance between her husband and herself.
She worries a lot about their future. She worries what will happen if--when, she knows it's when--the storm hits and Clark is exposed.
And it's not just Clark. Jonathan's not invincible: farm accidents happen every day, and he's already five years older than his father was when he had his first heart attack.
She's been working to keep her family safe for years, and she'll keep doing it, as long as the weather stays calm.
Martha gets out of Lionel Luthor's bed and goes into the bathroom. She's got to be home by ten. It's part of her routine.
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