Not really, depending on what type of text it was she'd reply instantaneously. Also, honestly in this day and age is it really appropriate to take at minimum 4 days to respond to a question from your "significant other"? That is not normal. Everyone is always on their phone, like she was. In any case, regardless of whether she was faking it or not, it's difficult to maintain a relationship with someone who is always either unavailable or unreliable. Eventually I start to mimic their stiffness despite how well intentioned I may be and how petty I may think my actions are.
> Also, honestly in this day and age is it really appropriate to take at minimum 4 days to respond to a question from your "significant other"? That is not normal. [emphasis added]
This is the real problem. Once you're dating someone (that is, it's past the courtship part and you've acknowledged the relationship), if you can't check your communication devices at least once or twice a day for messages from them (excluding hectic work/life schedules), there's a problem. You're continuing the game from courtship, you don't respect them, or you aren't actually into the relationship.
EDIT: Added 'once or '. I realize this is a YMMV moment, but even if you don't carry your phone during the day (like me), you can check it when you wake up and before bed. And if you're interested/invested in someone, you've got to make more time than that or there's never an actual conversation.
I once dated a girl who had two jobs and a kid. I frequently wouldn't get responses back for days. I tried to keep it going, but it fell apart after four months of one date every two or three weeks. In retrospect, I'm glad it did end, even though I was super into her.