I will tell this primarily because you are playing 5th and this is true.

Play your character consistently however you think best and don't care about alignment labels. They don't matter. All the mechanics that were tied to alignments back in 3.5 apply to creature type in 5th ed. So you could be the saintliest saint who ever sainted and Detect Good (and Evil) would still not care about you because it is looking for Celestials and Fiends (and Aberrations, Fey, Elementals and Undead).

That being said, pragmatism is not necessarily an aspect of neutral/evil, it is an aspect of sensible thought. A good character is by no means obligated to rescue people from their own bad decisions specially when there are other, pressing threats to other people who did not put themselves at risk out of stupidity. So don't worry yourself on that front.

In fact, that is an usual issue Good characters and their players appear to meet. Failure to help everyone everywhere every time due to simple lack of omnipotence being conflated with a failure to live up to "Good". The proper answer to that simple, inevitable truth is to tarnish the shining armor, not to start wondering if the G should turn into an N.