Lois is a kindred spirit in the sense of what she believes in and does and that makes her attractive in a way that Lana never would be able to attain.
The first time he met Lois she walked up to him and planted a kiss on his lips that was probably more passionate than any kiss Lana had ever given him. Of course, it was not this Lois, but canon-Lois, but it was a Lois.
When This Lois was introduced to his abilities for the first time, she tried to get him into her bed, or at least her bathroom. Well, at least that is what it seemed like to him.
Heck, with this Lois she is trying to get him into her bed the day he rejects her in his alternate persona. Nothing at all like Lana.
It sounds to me like there was a second incident, after the one with Walt, that really hurt Clark's Lana as well.
