I don't quite understand why she used "how" here? Isn't it more right to say "that" instead of "how"?
Native speaker’s answer
Rebecca
"How" is used in this case because this sentence is an indirect question. "How" is often placed after verbs like "know", "wonder", and "think" to express a question, although it is indirect. In this case, since the verb is "think" and since this sentence is asking an indirect question by wondering about life with her and the baby alone, it is correct to use "how". Here's a couple examples of "how" in the case of asking indirect questions: Ex: I don't know how she has the time to cook with her busy schedule. Ex: I wonder how they can afford to buy that car.