Tax question involving a sale of a home.?

My wife and myself bought a home 24 years ago. We only lived in it for 4 years. We bougt another one to live in and had that one as a rental. We paid 25,0000 for it and sold it for 18,000. The home was completly paid for as you can see we took a big loss. we sold the home due to or divorce. All money was divided. I was told that all the money had to be claimed on my federal incolm tax. Will this be considered incolm even though we took a loss? How much of a % ? A nother note the rental propery was empty for 5 years.