I am afraid for my family but have been doing research and don't know where to go? Will it be safer to just buy a new one?

You should have a HVAC repair man take a look before you start thinking a new furnace is in order. How old is the unit and what brand?

It sounds like your family is being tormented by a demon. Please move out of the house, for your family's sake.

Hope that sheds some light on your situation