I have gotten the hot water pipe loosened from the faucet but can't get the cold water one off. I have lubricated it and it is such a tight space I can't get pliers or wrenches on it. What do I do?

it is such a tight space I can't get pliers or wrenches on it. What do I do?
The first thing you do is get the right tool for the job. A basin wrench,(see image) is what you need for those tight spots.

Now tell me what nut's giving you a hard time. Is it the nut connected to the angle stop? The nut securing the faucet? In any case the basin wrench will solve your problem. Good luck, Tom