One great way to balance it, when their LL is AOS and yet you suspect infidelity (or even if they're just walkaway) and you don't want to "pursue":
Do an AOS -- one that's likely to be important to them -- but NOT the one that they told you to do.
In other words, ACT -- don't RE-act.
Be "leading."
Wash her car. Or pull it in the garage for her late at night, when she's left it out and she's fallen asleep on the couch. Or repair -- and paint -- a favorite room, but NOT when it's been given to you as a "honey-do" item.
Just find something to do, and DO IT. It doesn't even have to be big. Just something that says "I care for you," and that conveys love to her in HER love language.
Also, if they ARE wayward or walkaway, I wouldn't do this more than maybe once or twice per week, and I'm talking more "pull the car in the garage," or "cover her up with a blanket on the couch" than I am the big stuff even.