New fathers and infidelity

I see a lot of posts where people have young children and their WP has had an A shortly after birth, during pregnancy etc.

I wonder if this is common and I’d be interested to hear how many of you this has happened to.

I truly believe the birth of our first child led to my WP feeling ‘left out’ which led to his A. He says he thought I didn’t want him.

As mothers, we are completely selfless and put our children first. This is what I did, and any time she was asleep, so was I (I do also have health complications as a result of birth so this means I need to rest as much as I can). I truly believe this is what has got me through the first year as a parent but it’s what also led to my WP stepping outside our relationship. His EA/PA started just before my baby turned 1.

I don’t feel I could have done anything different, but can see how and what happened in his mind.