Jodi Tandet, the answer to this question depends on a few factors.
To start with, I would ask them if this situation has a negative impact on their lives at all? If they never had a libido, they could live a perfectly happy life as long as they do not decide to have a partner that expect to have sex with them.
I would also ask them what they mean by never having a libido. Does this mean they never felt attracted to anyone? Never enjoyed a sensual touch? Different answers might mean different things.
Many people think that libido means spontaneous arousal which is a desire for sex that arises from a very subtle trigger (like an image, a smell, etc). Turns out that there’s a very big percentage of people — in particular among women — that have a responsive desire pattern. Meaning, their libido kicks in only after a much more intense trigger (like, a partner lovingly and passionately making suggestions to imply they want to have sex).
I hope this helps and feel free to ask a follow-up question.