A woman who is into you always treats you as her first. You would be the first to know anything about her.
But when another guy fills that gap, that means your relationship failed to be emotionally grounded.
Comparison
A married woman would never compare her husband to another guy. When this happens, it means that you have not secured the necessary emotional connection she needs.
Comparing your effort to a guy means her heart is fixated on the attention she got from someone else.
Does Nothing to the Attraction
When a married woman doesn’t want to acknowledge that this level of attraction is affecting the relationship, that would grow into getting hooked on another guy.