I can see how NRE is creepy from both sides; for the secondary you would feel used, for the primary you would feel fake.
I'm a primary and my wife is flush with excitement around D, even though D has turned her down, and I have started playing Go with D.
That might in fact turn out to be a bad idea if it breaks my wife's heart because D and I would be best friends and she just has to suffer through being close, but no more, and watching all of that NRE evaporate as time passes. Rather, there isn't even real NRE at this point, just the promise of, the excitement, and the possibility of it just because they get to hang out when D and I are together.
She is seeing someone new, R2, that has been courting her through OKC. I'm not sure how that will turn out since her first date with him was yesterday and she hasn't talked about it yet.
In any case, I'm trying to defend the NRE, because I can tell you that just watching her with D brought back a rush of memories; how she would look at me and talk breathlessly when we were first dating, and reminded me how much I loved and still love her.
She has since turned her loving gaze on me in the same way, and I was filled with joy.