The old rule about pushing losses and gains forward into the next house was eliminated years ago. The sale and purchase are treated as two separate transactions.
Losses aren't deductible on a personal home. If you have a loss, you don't need to report the sale on your tax return at all, unless you also used the home for rental or in business or home office. In that case, you could owe depreciation recapture even if you have an overall loss.
See this for more on how to figure your gain or loss,
https://www.irs.gov/uac/about-publication-523