In this Star Trek episode, the crew visits a planet which seems a lot like Earth, but it turns out the inhabitants have a life span of only 30 days, if I remember correctly. Since their life spans are so accelerated compared to Earth's inhabitants, they are very quick to fall in love with the Enterprise crew members. After all, they expect to die within just a few days.
Did I dream this plot? I can't find any reference to it.
This question is answered! Thank you. The TV show in I was asking about is actually from Stargate SG-1, season 1, titled "Brief Candle."- Raoul Snidjiik