From singles to divorcees, collectively we are struggling to define what we need and want from long-term partners. — Lover, best friend, roommate, co-parent, sous chef, travel partner, chore sharer, driver (or driving companion), travel agent, accountant, general contractor, therapist, tax preparer, life coach, gym buddy, someone to go to the movies with…and anything else you can think of. Do we really expect the same person to know how…