It’s because attraction,like every other feeling,is a part of the human emotion and it is usually an indication of something if a person is not able to feel it.
It can vary person to person and across different cultures.
Eg:not everyone is romantic by personality and not everyone feels “big chemistry and sparks” -for some people it’s more subtle but generally most people can feel some sort of attraction or desire for other person.
Celibacy is more a person first having those desires,but then choosing not to act on them.
Even if you went to a doctor I doubt there is much they could give you tbh.Unfortunately much of this is still under research and there are no medicines given for social behaviour.
Some sort of cognitive/autism type therapy might help but to work it would be dependent on you being able to perceive those feelings in others in the first place (in movies etc).
It’s true that a lot of society is built around obsession with sex and romance but I don’t think that’s why people mentioned about seeing doctors.
It’s probably more that posters don’t want to see you miss out on a part of life that brings joy.
Regardless,your not alone even if it doesn’t change and I have heard of other people who feel this way but still have happy marriages

You might find a guy (I presume your a girl?) on a friends or hobby basis and it might lead to marriage.
A lot of people place huge importance on chemistry in relationships but chemistry can sometimes fizzle out as people get to know each other better.
I read this beautiful story about a Catholic widowed priest who married a woman with Schizophrenia in his youth.
He still fell in love with her despite the condition.
https://www.catholicweekly.com.au/from-rich-to-poor-married-to-priest/