Here are some possibilities based on the structure of the phrase:
* To be alone: It might be a playful or casual way of saying someone is by themselves, similar to "to be solo" or "to fly solo".
* To do something alone: It could be a way to describe someone doing something by themselves, such as "He's loning it on his road trip."
* To feel lonely: It might be a more informal way to express feelings of loneliness.
Without more context, it's difficult to definitively say what "to lone it" means. If you provide more information about where you heard the phrase and what context it was used in, it might be easier to determine the meaning.