I met my ex wife in 95 and married in 2001. Early on I’m my marriage I was almost a WS. I got into an EA with a woman at work and contemplating briefly ending my marriage. I ended the EA and went on to starting a family with me ex w. Years afterwards looking back thinking of the ea literally made me sick to my stomach. My son was born in 2004 and daughter in 2008 and up until the fall of 2014 we had an amazing life. I wouldn’t trade those memories for anything. I won’t look back and say the last 24 years was a lie or a waste or anything like that. Just the last 3 years we’re horrible. The reason why they were horrible was because I was trying to hold onto to something that didn’t exist anymore. Our marriage was simply because she didn’t want it anymore. This didn’t mean she regretted the last 24 years either. Just that moving forward she didn’t want to be married to me anymore.
It’s not uncommon for a WS to plan their exit strategy 2-3 years prior. I would try not to take it personally. People change and relationships run their course.
What I will agree with you on is that your W is a pretty $hitty person with low integrity and you can use that to fuel your recovery. You will survive this that I am sure of right now.