I'd be really tempted to go to Tahoe, and let him have the kids Monday. It sounds to me that your friend could be a great source of support. Also, it would be a bit, or more than a bit of a GAL activity. It would also give him a bit of responsibility, and the time he spends with the kids might actually help you in the long run.
It's a bit of a tough call, but that's how I lean!
