Welcome to SI and I'm sorry that you're joining us. In the JFO (Just Found Out) forum, there are some pinned posts that we encourage new members to read. The Healing Library is at the top of the site and has a lot of great information, too.
One piece of advice we give for those who want to R (reconcile) is that any friends who are not friends of the M (marriage) and facilitated or encouraged the A (affair) are cut off. He shouldn't "limit" communication, he should entirely never contact the old buddy.
Your WH (wayward husband) should read How to Help Your Spouse Heal From Your Affair by Linda MacDonald. (You can read it, too.) Another good resource is Not Just Friends by Dr. Shirley Glass.
If you can, IC (individual counseling) with a betrayal trauma specialist can be helpful. Your WH needs IC to work on becoming a safe partner. Too bad that it makes him "feel bad" - he needs to work on the reason he feels bad and to find better coping mechanisms.
Please be sure to get tested for STDs/STIs. If you're having trouble with anxiety or sleeping, ask your doctor for some meds.
It takes years to heal from betrayal trauma, so this isn't a case of you "not letting it go", you're trying to heal.
ETA: Tell who you need to tell, including your adult children. If they're adults, they can maintain their own relationship with their dad.
[This message edited by leafields at 3:28 PM, Thursday, August 21st]
BW M 34years, Dday 1: March 2018, Dday 2: August 2019, D final 2/25/21