My neighbor keeps using my driveway because "I don't need all that space"
I moved into my house about 6 months ago. I love alone, and my driveway has enough room for 2 cars. I only own one. A few weeks after I moved in, my neighbor asked if his girlfriend could park in my driveway for one evening because they had family visiting. I said yes. I thought it was just a neighborly favor. Apparently that became permanent permission. Since then, I've come home multiple times to find either his car or his girlfriend's car parked on my side. At first I tried not to make a big deal out of it. I would just park around them because I really didn't want to start problems with someone living right next door.
Eventually I politely asked him to stop. He seemed surprised and said, "But you only have one car". I explained that it's still my driveaway and sometimes I have friends or family over. He agreed. 2 days later, his girlfriend's car was there again. I knocked on his door and asked if she could move it. Je got visibly annoyed and told me I was being difficult for no reason because the second space is "literally empty 90% of the time".
What really bothered me was when he said that since I live alone, he doesn't understand why I'm so protective over space I'm not even using. Now whenever we see each other outside, he barely acknowledges me. His girlfriend moved her car, but they've made me feel like I'm some petty neighbor who created drama over an empty parking space. I genuinely tried to be nice when they needed help. Now I regret ever saying yes because apparently one favor turned into them feeling entitled to part of my property.
Maybe the space is empty most of the time, but I don't understand why that means someone else automatically gets to use it.
TL;DR: I let my neighbor use my driveway once as a favor. He and his girlfriend started regularly parking there without asking and now think I'm being unreasonable for stopping them because I love alone and have an unused space.