You think that something is wrong, when in fact nothing may be wrong. Perhaps you have yet to meet the right person. That’s what dating is all about. You meet someone, you get to know them and if you don’t like them, you end the relationship. That is how it works. You choose one to marry but only after rejecting many. It takes time to find the right one.
You seem to have expectations or assumptions about love and relationships. I wonder if you are judging yourself against arbitrary standards and inappropriately determining that you don’t make the cut. Perhaps your ideas about love and relationships are based upon popular culture and if so, they could be very skewed. What you see in movies doesn’t accurately reflect real-life relationships.
Abraham Maslow writes about the nature of interpersonal relationships among the most psychologically healthy people. He finds that they have especially deep relationships with few individuals. He notes that their circle of important people is rather small. That’s because getting to know someone on the deep level is time-consuming. “Devotion is not a matter of the moment.” Deep, meaningful relationships — loving relationships — require a great deal of time. They are more demanding when compared to other types of relationships.
You don’t want to waste your time on someone, you have determined through dating, who is not a match. Based on what you have written, you seem to be doing all of the right things. If you continue to be concerned about your ability to connect with people, consult a therapist. An evaluation by an in-person therapist may bring you peace of mind in a way that my internet answer, with all of its generalities, cannot. Good luck.