Your light exposes something inside of them they’d rather keep hidden in the darkness. So, of course, it’s offensive to them. It’s painful to feel exposed. It’s only natural for them to lash out, but they are just trying to turn off the light as quickly as possible. It’s not a personal attack against you (although it will certainly feel excruciatingly personal at times). It’s an attempt by that other person to protect whatever illegitimate ways they are getting their legitimate needs met.