I have seen water pressure increase and decrease due to a bad pressure regulator.
The problem that you describe sounds like you have a restriction in the water supply comming into your house. This could be due to sediment that has built up on the inside of the main waterline, sediment that has become stuck against the seat in the main shut off valve, sediment plugging the screen in your pressure regulator or a bad regulator. If you are seeing 110 pounds of pressure, this would indicate that your regulator is not functioning properly and it is allowing pressure to creep up past the set pressure.
I would exercise the main shut off valve several times with water turned on somewhere down stream of the valve. This could help flush out any build up against the valve seat.
I would clean out the screen in the pressure regulator. If these things don't help I would replace the regulator.