Can low blood sugar cause a person to act "disattached" and not have a good understanding of theirsurroundings?

Yes: Low blood sugar can make you confused and not aware of what's going on around you. In severe cases, it can make someone pass out completely. The only way to prove this is to check the blood sugar with a glucometer.

Absolutely: These symptoms are due to decreased glucose delivery to the brain cells stemming from hypoglycemia, hence the alteration in focus and alertness level.