It's common especially with those who have fallen into a pattern of embracing and enjoying the lack of a partner.
Most of these articles advice you to go out, meet people; they advise on your grooming and dressing and all that.
But sadly, people sometimes remain single because somewhere along the line of being single to stupor, they shut down their emotions and became inaccessible.
This is common especially for those who have fallen into a pattern of embracing and enjoying their 'boolessness'.
They become so used to it, so comfortable on their own that it becomes quite uncomfortable to begin a relationship and let someone in who will 'disrupt' that balance they have found in enjoying life by themselves.
This is how you'll know you belong in this category:
As your date partner tries to familiarise himself with you and tries to know you better, you feel like he's violating your privacy by prying.
You don't even want to flirt with anyone, and when someone tries, you roll your eyes and scoff at their attempts.
You are only about the physical gratification than the emotional connection sex brings.
You just want to rip your shirt off and get down to it. Nothing about emotions, you just want to cum and move on with your life.
For you, making eye contact with the opposite sex is too much mushy stuff than you can bear so you avoid it at all costs. Of course it does not make sense.
Whether it's a case of PDA or mushy conversation, it bothers you.
When your friend, brother or sister speaks about the partner he/she has just found or how great it is to be in a relationship with such person, you can't relate and frankly, you don't care.
You'll just wish the person would shut up and let you rest.