Why are older single women always regard as crazy cat ladies?

Meanwhile an older single man is called a bachelor (nicer name), a woman is always referred with the derrogative lable as ''the crazy cat lady''. Why?

Not all single people want pets either. Everyone isn't the same. Not everyone single is crazy either.

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+1 y
There are many reasons why she can be single. Maybe she can be asexual and never had attraction towards anyone and is happy with her life. Not necessarily crazy.
Why are older single women always regard as crazy cat ladies?
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