Now do you have an electronic thermostat that you can turn off/on, go on low? That has helped us.
We are in a 2000 sf house,/ 3 bedroom/two story.
We had a full tank of oil the day we settled (Dec 19), and we got to 1/4 tank On 3/15. (yes, almost three months!)
We paid 1.69 a gallon for 100 gallons, and we are now at 3/4.
We have a 375 gallon tank in the basement.