There are many different kinds of single people. Some have never married, others are widowed, separated or divorced. Some have turned down opportunities of marriage, others have never had such opportunities. There are singles who long above all else for marriage, and those who abhor the very idea. Some singles see their singleness as a special call of God, others as a cruel curse.
Singleness is difficult.
So is marriage. For those who are content in it, the single life can be deeply satisfying and a great aid to ministry. This was Paul's experience. And ultimately the Christian experience is learning to be content in whatever circumstance, and whatever marital status, you find yourself in. Even though you are single, you don't have to be alone.