How do you think she reacted when she woke up 9 months pregnant? What about one day (everyone one of them), when she wakes up and discovers she's old?
Or when she woke up and found herself giving birth, or when the baby woke her up in the middle of the night?
Oh, it's worse than that. Imagine going to bed as a teenager every day then waking up to meet a little girl and middle-aged man that you've never even seen before who claim to be your daughter and husband, respectively. Imagine BEING a child of such a parent. What will happen when the daughter hits puberty? What happens when her daughter invites a friend for a sleepover? What if she goes to one?
It is never explicitly stated in the film that Lucy gave birth, but if she had, what she experienced the day her child was born was almost certainly akin to the final scene of "The Almost People".
Not to mention, when her father eventually dies.
What about when Henry dies and she's got nobody to explain things to her?
Presumably, her kids will be old enough to take care of her by that time.
What do you think happens when she wakes up before Henry?
Presumably he is careful to get up early every day. It's not that hard.
Maybe they just don't sleep in the same bed. Keep in mind she's not relying on Henry to explain things—she's relying on the daily videos and diaries that she herself makes.