I think most of the problem is lack of "practice". If you have not been on a date, not been one-on-one with many people you can't have any clue as to what it's like or how to do it or what the big deal is. Think about when you were a child and had no clue about money or how much things cost (food/housing) and just sort of thought those things "happened" automatically? Relationships with other people are not any different. You have to be with other people, date a bit, see first-hand what it is about before you can know how you feel about it? You can't judge something and whether you'd like it or not for yourself if you haven't experienced it.

That's why I try all types of food at least once, to see if I'll like it; rejecting "broccoli" just because one's parent did/does is not that great a strategy unless you understand/acknowledge that is what's going on. That's how we can get into personal trouble as adults; only having other people's experiences that we witnessed in our parents or other adults to go on and not realizing that's why we are making certain choices in our own lives, rather from our own, actual, experiences.