Nice job acting "as if." Your friend has the right idea. Like an addict, there really is nothing you can do for him. He needs to figure it out himself.
As for strength, you really are doing well! Keep posting, stay active, mentally occupied and stick with your IC as long as you feel it moves you forward. You too will become stronger through this.
Me 41, H 47, M 15 yrs, S11, S13 BD 1: 11/4/14 we work on it; really I pretzel myself BD 2: 3/31/15 H goes down to "dorm room" 8/15: H back to MBR 10/15: H back in dorm room 1/18: H files, now divorced