Husband is "giving me equity"?

My husband and I are splitting up. Not particularly amicably. I will be staying in the house we owe on. In 6 years I have found out that my husband has only paid $5000 to the principal of the loan. Our payments have been about 450.00 per month. In six years this should come to about 32,400. Where is the other 25k if only 5000 has went toward the principal of the value of the house? I know about $3000 of it went to property taxes because they are rougly 500.00 per yr. But where is the other 23 or 4 thousand dollars if it did not go to the house payment??? How does only 5k actually get applied to the loan in 6 yrs? That is not even 1000.00 per year? He says he is "giving me the equity" and from there it is up to me to make future payments. What exactly does this mean? How can he "give" me the equity? Is it something I already have that is mine? Or is he truley "giving" me anything. We still ow 45k on the house.