Property gain on sale of co-owned property

We sold a co-owned investment property. 

I am the only person on the loan. Both of us paid for the mortgage. 

 

The property gain is 80k. I took 5k and he took 75k. 

I took a lost as i invested more than 5k. 

 

Am i supposed to pay for the property gain?

Will there be a 1099 form stated i only received 5k?