I fucking hate being single. But I've also lived in a hellish committed marriage, so I guess being single is the lesser of the two evils I've experienced so far. I'm suspecting there's no such thing as a healthy long-term relationship for me.
I love being single. I usually feel like I lose my identity when I'm with someone, like I have to give up too much of my own life & interests to fit into the other person's life. It gets uncomfortable and then it has to end, so I can go back to being me. In other words, I'm not good at relationships!