I Love her even more
This is based on a real event that happened many years ago. I told my wife about my cuckold fantasies and encouraged her to flirt with other men while we were at bars or parties. Afterwards we would go home and have really heated sex. My wife loved how turned on I got from seeing her flirt.
You know they heard you come in, because they both turned and looked at you very briefly -- but then continued with what they were doing as if you weren't there. After watching for a minute or two, you started to feel extremely awkward, so you just quietly slipped out of the room, and then went to stay the night in a motel.
This based on an actual event. My wife was pretty much the opposite of a flirt and if a guy even tried to flirt with her she would quickly deflect his advances. However, a few years after we got married I started telling her about my cuckold fantasies and confessed that it really turned me on when guys flirted with her. Gradually over the next several years she became more comfortable when guys flirted with her. We would always talk about it when guys flirted with her and I always encouraged her to flirt back and eventually she began flirting back.