Irritable thought. Explanations online!

I experience frequent and repetitive thoughts about love, relationships, marriage, physical intimacy and having children. These thoughts often arise automatically, even when I am doing something completely unrelated. For example, while watching a teacher's lecture, seeing someone on the street or spending time with my family, my mind suddenly starts wondering about other people's personal relationships and family lives. I find it difficult to understand why my brain connects ordinary situations with these topics so frequently. I constantly compare my thoughts and feelings with others, assuming that everyone else can accept these aspects of life naturally while I struggle with them. I also feel anxious about my own future and repeatedly question whether I will be comfortable with relationships, marriage and other aspects of adult life. I sometimes become uncomfortable simply by imagining these situations. I overanalyse my thoughts, question why they occur, search for explanations online