Learn English – better term than “fighting spirit” here

I want to say "he has no fighting spirit anymore" to describe the psychology that might be involved in scenarios when someone has behaviours like this:

• Hungry, but not to the point of overly weak, but still stays in bed because there's no food at home and he has no motivation to go out.

• Wakes up five minutes before a university class or examination, doesn't bother rushing to the lecture hall to at least glean a fraction of the exam time.

So in a sense, what I'm trying to describe might be somewhat poetically described as a lack of the will to fight or wrestle with the reality one faces (in that sure, "He" might go to class if "He" woke up an hour earlier, but he won't bother if faced with significant obstacles).

However, "fighting spirit" doesn't seem to quite capture this properly. For scenarios like this, "he has fighting spirit" would seem to imply too much of a metaphorical fight. While there's indeed conflict here (between the individual and "reality"), I'm very hesitant to describe the person who does run to her exam after waking up late as "fighting reality". Moreover, some of the connotations of a "fight" carry very poorly to this sort of thing.

Is there a term (perhaps a philosophical one) that might better fit the sort of mentality (or rather, lack of) that I'm talking about?

I considered "will to power", but my understanding of Nietzsche makes me believe that there are too many social or moral connotations. Similarly, ennui fails: lack of motivation doesn't necessarily equate to boredom.

Are there any better alternatives? Or am I wrong about the "will to power"?

Update: After I got some answers that described the situation but didn't seem to be what I was looking for, I thought about what the key thing I'm interested in is, and bolded that part.

Apathy and resignation work well here, and I like those suggestions, but I'm wondering if there's something better for describing what is lacking. (After all, while it's indeed true that the opposite of "she refused to accept the horrors of the world" is "she accepted the horrors of the world", I feel like the latter doesn't entirely convey what is going on.)