1. (literal): When friends or strangers keep giving you drinks without having to ask.
2. (spiritual): Drinking deeply from the cup of life, and then drinking some more. Accepting the Universe's plan and indulging in its bountiful offerings without hesitation or regret.
"My friends have been buying me drinks all night; this must be the bottomless lifestyle!"
"I've been living a bottomless lifestyle since Burning Man; I don't make plans, but things just keep happening, and I love it!"