I've been reading through your thread and think you're wise to:
1. Pack stbxh's stuff and have it waiting at the door 2. Make it YOUR space with new paint and accessories 3. Take class sooner rather than later
Show him that you're moving on with your life.
If he's having doubts, you turning off the lights on the NewMama option could make him freak. That + having him nearer his family + OW being further away from her family = a possibly quick end to their romance.
So what if he signed a lease? He can break it or sublet if things awry. It's a lease, not a death sentence.
Keep strong and see what happens. You're the girl!