Hi Patunia, and welcome to DC!
I'm not sure what you're doing, but I'll do some guessing.
Perhaps you're putting the BBQ sauce into the crock pot before you cook off the fat in the meats. Then the fat *melts*, adds volume to the BBQ sauce and *waters* it down.
There is a way to prevent this. Put only enough plain water into the crock pot to cook the meat. The meat doesn't need to be submerged in anything.
When the meat is 75% of the way to being done, lift it from the crock pot and set it aside.
Then ladle off all of the liquid in the crock pot into storage jars if you would like to use it on another dish.
Then add your meat back into the crock pot one layer at a time and liberally brush each layer with your BBQ sauce. On the top, pour enough to cover the surface of all the meat exposed to air.
Recover the crock pot and let it finish cooking. Test the meat with a meat thermometer for doneness. I stick mine down into the meat while its still sitting right in the crock pot.
If the meat is done, use a wide spatula or tongs to remove it without breakage to a serving dish.
The BBQ sauce should be near the same consistency as when you put it into the crock pot.
The meat fat can be used in tons of recipes and for gravies and sauces.