And when you get divorced, you’ll rediscover yourself and never change for anyone again. You’ll ask yourself why you changed and gave up activities you enjoyed while picking up activities you dislike.
This rings true to myself. While I thought I changed for the better, I did, but sacrificed all the things I really enjoyed doing. Best thing I did after 15 years was find myself again.
What I can’t discount is I’m a better version of myself than I was prior.
I think this doesn’t just apply to Divorce. I stopped attending a church after 20 years and rediscovered some things I’d given up because I thought they were “unbecoming” of a dedicated follower. On the other hand, there are some philosophies taken from that time that I am glad are part of me.
I would heed his prophecy rather than dismiss it per ad hominem, because it's an extremely common fate for many a man. If you believe you're special, that you're immunized from such a fate, you'll let your guard down, and when you get hit with your guard down, the hit comes harder.
I see we disagree about the likelihood of an easy to measure event. I'll bet you one dollar at even odds that I am not divorced from my current wife by 2028-12-21, UTC midnight. Considering you consider this outcome "extremely common" 1:1 odds is a statistical bargain for you.
The point is to not give up what makes you, you for another person, regardless how invested you are in them. And don't feel obligated to take on their hobbies, etc.