You are still so new at only 5 months out. One big thing is not to measure your healing against anyone else's. People are different in their reactions; however, it's generally said that it takes 2-5 years to recover from infidelity.
The healing is incremental, and not always linear, but someday you'll wake up and realize how happy you are.
I really recommend the book "Getting Past Your Breakup" and the book "Journey From Abandonment to Healing" is often recommended here as well.
Try to go as NC as possible. I see you have a rather young child together, so it won't be possible to go complete NC, but there are other parents here who can give you tips on what works/doesn't work for their situation.
As for your social circle, I don't know details, but I'd seriously look into making some changes there. I know I would not continue to be friends with anyone who wanted to be friends with WXH/MOW.
Arrange your life for success, and that means limit your exposure to toxic people.Me: BW, divorced, now fabulous and happy!
Married: 11 years, no kids
Character is destiny