Do you have a Sleep mode implemented that differentiates Night time from when you are actually sleeping? I have a sleep mode and it makes things a lot easier.
If you do, have a rule that is restricted by mode to Sleep only.
Condition: Switches on
If true- Disarm
If false: Arm Sleep.
But also, are you actually opening doors when these lights are on? Because if someone breaks into your house and turns on a light, the alarm will disarm. That's not a very secure alarm system. I have 3 modes for HSM, home, away and disarm. Home is contact sensors only, away is with motion. Very simple. That way i can get up in the night and move around the house without fear of setting anything off.