You can move your modem to any active cablejack. Your Comcast modem should not have anything to do with a Direct TV box.
OR........Tell your boyfriend to stop disconnecting the modem, problem solved.
If you are not familiar with how to get this done, I'd prefer to have a technician scheduled for you for your safety and to make sure the services are working correctly once this process is completed. Can you please verify your first and last name, full street address, and the phone number or account number associated with your services in a private message?
To send a private message click on my name "ComcastChe", then click private message me.