This was a mistake.
As regards leaving the house, once he gets used to the idea that you aren't coming because he whined, he will calm down in his crate. Since you came to him when he whined in the night, he thinks whining brings you back, so of course he's going to whine when you leave. Just start ignoring the whining. Don't go to him or even look at him or let him out of the crate when he's whining. What you need to teach him is that whining doesn't do any good, so it's wasted effort. Then he will stop.
Good luck!