I'd be recording what S reports by date. Memory isn't the same, and you don't know what H will do in D proceedings. Hopefully, it will be unnecessary, but better safe than sorry.
Have you considered mediation? If he wants D & separating your lives more fully, tell him that you aren't wanting a divorce, but if that is where he wants to go, you'd prefer to go through mediation to keep it as cooperative and non-conflictual as possible. If for no other reason that it will be better for the kids if their parents are getting along at the end of this.
Then find a mediator with a therapy background rather than a lawyer. You want someone who is attentive to the emotional side of things and can take opportunities to improve the relationship when they come along, rather than just settling the D quickly and less oppositionally.
Me: 50 W:43 S6, S3 M: 12 yrs. T: 17 M is bad & Not happy Bomb Mar '14 S 5 Feb '15 D Bomb 13 Apr '15 (but "no hurry") DB Coach May '15 Wants proceed on D Aug '15 Starting 1-on-1 negotiations Sept '15