is socialization good?

Yesterday walked with an unfamiliar girl. It was not bad, but I could not understand my emotions.
I am frightened by the development of this relationship. Now everyone is so easy to have sex with each other, it's not close to me. In general, physical proximity is a great stress and sensory overload. And I do not want to sleep with someone other than my girlfriend. Perhaps this is love. I feel an emotional closeness to her and I understand that it seems I would like to spend my whole life with her. With her, I felt joy and happiness.
But other girls are difficult to perceive as casual partners. Friends say that I stupidly act, but they do not fully understand my feelings.
But I also do not know whether Nastia wants to continue with me or communicates out of politeness or pity.
Relationship is very difficult, maybe I really need a psychologist who will help get out of my head and stop reflexing.
Do you think it is normal to communicate with a person and not to sleep? Is friendship possible without sex, it does not make sense for ordinary people?