That's the point of this side story, Keith is now on the same spot yeonwoo (kimda) was. He's learning more deeply about what it meant for yeonwoo to be an omega, he's showing how much this relationship means to him since I the beginning he has no care in the world. I'm glad we get to see him suffering a bit although I iwhs it was more...
Not to be rude but why are you explaining the plot to me... I know what's happening...
Since you say that Keith should stop being insecure and focus on being a better husband, I wrote it to basically explain why Keith being insecure is important to the plot. And why it's leading to him learning to be a better husband. It's not that you don't know what's happening but i wanted to highlight it.
Gees Keith insecure much. Maybe you should focus on being a better person so you can be a better partner instead of background checking your husband. Especially considering the person you're freaking out about is you! Ha.