Extramarital Temptation

Recently found myself feeling too comfortable/complacent in my marriage. Discussed with my partner and they disclosed feeling comfortable was a good thing - obviously not seeing eye to eye on what that meant.

This conversation was sparked when I realized my attraction to someone else was not waining as a typical “crush” would. We started couples therapy to help with communication and getting on the same page. It’s going great and I adore my partner. I am (mostly) happy and very in love, but still dealing with this temptation outside of my marriage. Felt the need to disclose “mostly happy” because I do think that is a factor in this fantasy of another person.

I am trying to be very intentional and pour my attention and effort into my current relationship but it’s defeating to see this other thing still exist in such a strong way. I know temptation is normal but wondering how to identify when it’s just temptation vs actually searching for something else? I have the strongest urge to cheat, probably because it’s new and exciting, and it’s really concerning for me.

Looking for advice, rude comments aren’t needed.