The normal state for adult life is to be married. One way of giving this over in presentations that audiences enjoy is my "samurai and baseball" analogy.
In Heaven, a soul is created. The Talmud tells us that a human being is a husband and a wife, together. Before one is married, he or she is only half a human being, a male half or a female half. This is why one feels loneliness for a mate. It's like having "your better half" surgically amputated from your complete self. Would it feel good to have that lost part restored!
After this total soul is created, Heaven hires a skilled, expert samurai swordsman. His sword is very sharp. He has practiced for decades to become a precision master. Heaven's assignment is for the swordsman to slice this total soul right down the middle and divide this soul precisely into its male and female halves.
He gets ready. He lifts his sword in the air (or in whatever they have "up there!"). He gives a big Japanese scream (called a "geshray"), "Eeeyaaaaaaaaaaaaaaaaaaaaaah!" He makes a precise slice that divides the soul into its male and female halves. Now, Heaven sends each half down a chute to earth, one to become born a baby boy, the other to be born a baby girl. They grow up. They get old enough to date. They have longing for their lost "amputated half." They reject wrong souls (or at least, hopefully do - because wrong halves don't work out with eachother). They are not the precise size and fit for the half that each one constitutes.
Through divine Providence, G-d manages the events so that when the time and circumstances are ready and perfect, the two half-souls are brought together. Their wedding is the "surgery" that restores the two severed halves back together. On paper, at least, it feels great. Each partner tackles various functions and responsibilities of life so that, in total, they operate together as a complete and effective entity.
To illustrate, imagine a baseball game. Most people are right-handed so they hit the ball to the left. A lot of balls are hit to shortstop (which is on the left side of the playing field) so it is an important position. The guy playing shortstop decides he isn't in the mood to stay at shortstop. The sun is too direct. Too many hits go just left of middle. He has to work too hard. He decides he needs to go to right field where the fewest balls get hit. So now there are two guys in right field and no one at short stop. The opposing team hits a lot of balls to shortstop and there is no one there to catch the ball and get the batter out. The other team is doing "gangbusters," hitting run after run after run. They just keep hitting to the vulnerable, uncovered shortstop area. Now, the pitcher gets aggravated. What's he accomplishing by having all these runs hit off of him? So what's he going to do? He's going behind the plate and be a second catcher. Two catchers, no pitcher. The game is at a dead standstill.
Marriage is a team. Each "player" has to assume his or her positions as needed for the team to function. All the positions THAT THE GAME OF LIFE REQUIRES MUST BE COVERED BY THE PLAYER BEST EQUIPPED TO EFFECTIVELY HANDLE THE RESPONSIBILITIES THAT EACH POSITION REQUIRES. Otherwise, the game of life will overwhelm your team (like when the shortstop left for right field) or the game will come to a dead standstill (like when the pitcher went to catch). Nature puts inclinations, proclivities and abilities into the male and female, equipping each to occupy positions more effectively than others. Some players are better equipped to handle certain positions, with their respective responsibilities; while others are better equipped to handle other positions, with their respective responsibilities; such that, in sum, all the positions should be effectively and successfully covered SO THAT THE MARRIAGE TEAM CAN FUNCTION IN, AND WIN, THE GAME OF LIFE! The one soul, with the male and female halves, expresses that unity in practice, by the sharing of a common mission together, and each
half cooperatively and cheerfully fulfilling the elements of that mission to which each half is best disposed.