Happening to me too. Brand new game created about 2-3 hours ago, loaded into the very first family in willow creek(spencer kim lewis). Alice asked Eric on a lovestruck date I said why not and picked the library in san sequioa. First off their kid came with for some reason even though she was not on the invite, second neither of the sims when flirting with each other counted for the date activites and then it just ended for no reason after no prompting from me.
I thought that was odd but just chalked it up to the usual buggy game. Sent the kiddo home and recreated the date. Alice asked how Erics day was and then date ended no reason no prompting just over and unsucessful.
All are active sims in the same household controlled by me.