Joanna's marriage to Romain Zago is officially over ... and it's hard to imagine a divorce going more smoothly. Neither side sought spousal support, and we're told they split things up evenly -- she keeps the L.A. pad and he gets the house in Miami. Romain also gets visitation rights ... for their dogs.

Joanna tells TMZ ... the 2 are grateful for their time together and "wish each other nothing but continued happiness and success." She also says she's taking time for herself and focusing on her projects, and hopes their amicable divorce can inspire others.

This comes on the heels of Krupa and Brandi Glanville reaching a settlement in the infamous smelly vagina lawsuit ... which Joanna also hopes can serve as inspiration.