I've never been in your spot, but I would think I would want:
- space enough to focus on his new job instead of the R
- encouragement with the new job, some kind of congrats that only you, his mother, or another close person could give him
- when you see him pretend you were dating him again
- be confident
- forgive and forget, for now at least
- be strong so he knows you don't need him, you want him