Agreed with Mr. Bond. Try to separate parenting together from healing your marriage. You will parent together no matter what happens between the two of you and there is nothing wrong with that, as long as you aren't using family outings as an excuse to get time with your wife.
If you had a children's party at work and a function at church, you can tell your wife you're going to take your son, there is nothing wrong with that. If she wants to come, let her bring that up. You're not inviting her, but you're not leaving her out either. You're telling her what your plans are for your son, let her do with that what she will.
If it comes to childcare (illness, daycare, school, etc.) don't hesitate to call her. Just keep it about your son and do your best to resist sliding in comments about how much easier things would be if you were together, etc. For now, keep it to "just the facts". Acknowledge that it's hard, and know that you will slip up. No one is perfect and this is an extreme challenge.
Accuray
Married 18, Together 20, Now Divorced M: 48, W: 50, D: 18, S: 16, D: 12 Bomb Dropped (EA, D): 7/13/11 Start Reconcile: 8/15/11 Bomb Dropped (EA, D): 5/1/2014 (Divorced) In a New Relationship: 3/2015