Another word for being single is FREE.
Free to do what you want when you want with whom you want.
However if what you really want is to be "attached" to a special someone and buliding a life together then you most likely will not think being single is better.
No matter how you look at it there are people who are single and happy as well as those who are married and happy. There will also be people in both groups who would gladly swap places.
Happiness comes from getting the things we want most out of life. Whatever works best for you is better!