How is her new stall different from her old one?
One thing that has worked for me on trailering is to either leave, or place, poop from her buddy in her stall. Just toss a couple of piles in there and leave them. It might make it smell less foreign to her and encourage her to enter. Otherwise, just keep working on getting her to relax about it and enter. I'd halter her and lead her up as close as she'd go without tension. Then stop and wait til she is totally relaxed, then ask for 1 or 2 steps and stop once you get them. Pet her and go away. Come back in a couple of hours and do it again. It will take what it takes, you're on horse time, not human time.