I agree with Beatrice: I think it is important to distinguish between actions that you do that distance your S from his father and actions that your H does. Obviously if your H is not taking an interest in your S, that is his loss.
What is it about FB that is sooo difficult to resist? I blocked my W and OM to eliminate any temptation to check. I am really struggling to detach. You might consider doing the same if it is causing you to obsess.
