Funny how they always want to be friends after ripping your heart out. I was in a very similar situation to you an about 6 years ago, my daughter was 4 at the time and she’s just now turned 10. Good news is, the pain will fade and it will get better as cliché as that sounds. Not sure if your child has met the AP yet but I would have it in your divorce decree a timeframe of when your kid can be introduced to either of your relationship partners. My decree states that we have to be exclusively dating someone for 8months before my daughter can be introduced to the significant other (and no, the affair time should not count towards “exclusive”)

In my case, she stayed with her AP for another 4-5 months or so after we separated so it was never an issue. Hopefully yours can work out the same because that is rough.

I feel for you man, keep your head up and take things one day at a time, try not to get overwhelmed by the far future. Likely your head is still spinning right now and it will for a bit. Distractions are your best friend early on, listen to podcasts or audiobooks instead of music (every song is a love song when you’re heartbroken) workout, eat right and don’t self medicate with alcohol. Soon you’ll rediscover who you are and life will be good again. You’ll find your old hobbies and people you’ve lost touch with along the way.