This was a dream I had a few months ago but still remember vividly because of how much it affected me. I was still with my now-ex-girlfriend at the time, and in the dream we were at some kind of fancy hotel/restaurant having a meal. It was established that this was a post-apocalyptic world in which no one had sex, in fact the concept of sex had long since been forgotten. After our meal we decided to go and explore together and found a door leading outside. The hotel was on the edge of a cliff/canyon in the middle of a desert, and the door led out onto a small ledge in the cliff face. We decided to climb down to a lower ledge where we could see a way in to an abandoned basement of the hotel. Inside we discovered some old books from before the apocalypse which happened to contain references to sex. Naturally we decided to 'try it out' and it was implied we had sex, although I don't remember it (I think the dream skipped ahead like a PG-13 film 🙁) After our fun we decided to leave and head back up to the main hotel, but it was harder to get back than we had realised. It was now dark and a strong wind had started to blow which threatened to blow us away if we tried to climb back up. We couldn't get back into the basement for some reason so we were stuck on the ledge. While we were trying to figure out what to do I noticed a movement further down the cliff. It was too dark to see at first but then I saw a shape run between two rocks at the bottom of the cliff. I only saw it briefly but it still haunts me. Basically it looked and sounded like the fast zombies from Half-Life 2 but with the headcrab removed (google it if you don't know what I mean.) Somehow I knew there were lots of them and that they could climb up the cliff. That's when my gf and I started to panic, shouting for help but the wind drowned out our voices. The wind got stronger and my gf slipped and fell. I grabbed her by the arm and tried to hold on but I could feel my grip loosening. That's when I woke up. I'm usually quite good at waking myself up when dreams start to go bad but this one went way further than usual. I was pretty shook up and I can still feel how scared I felt if I think about it now. We broke up shortly after that so I guess maybe I felt like our relationship was ending and I was struggling to hold on to her, hence the ending of the dream.