Why is being single so hard?

I honestly don't understand. I'm 25, not overweight, have a career of 6 years, not looking for marriage, do whatever I want, and being single is A HARD. I mean, I know I'll be single forever if that's what it's for, but it's so hard. I have one friend. ONE. I don't know how people do this. I don't buy I'm the only "broken" person. I'm so bored of being by myself all the time. I know it's part of being single...but when does being single begin to being enjoyable? I mean, I know the feeling of "I'm glad I decided to stay home tonight, being alone is better!" but is this really a good thing to claim?? I don't understand. I go on dates....I have a bunch of "friends" that never call, or reach out, and want nothing to do with me outside of social media. I don't know how people do this. I'm so bored of being alone all the time.