(Spoiler for Jones, and I'm kinda fuzzy on the whole Will/JJ timeline, so maybe a wee bit AU.)
JJ had always been kind of a loner. She liked people, there was no question of that. She enjoyed company. She had friends- not many of them close, but some- and she cared about them. But in the back of her mind, she really preferred to be alone. She liked silence, liked staring into space and thinking for hours on end. Sure, she was bubbly and friendly and sometimes that made people (read: sexist police chiefs) think she was dumb. That was not the case.
She wasn't unfeeling, the cheer wasn't a façade. JJ enjoyed her job and the people she worked with; she cared about them like they were her own family and she would be crushed if anything happened to them. There was just no one she wanted to spend every single moment of every single day with.
Then she met William LaMontagne, and what she felt for him was pretty close to that. The few days she could snatch with him on her rare vacation time were a tangle of closeness and skin and whispers, smiles and the bittersweetness of this-may-be-the-last-time, because with their jobs it could be. Next came the proposal, which she accepted in a heartbeat. After came the pleading, the requests for her to come live in New Orleans, but the city was too loud and unclean for her. Quantico was a suburb in comparison, quiet, groomed. It reminded her of home. After a month of pleases, she compromised, asked him to move in with her. His response, a drawled "Chere, I was just waiting on you to ask," made her heart melt all over again.
But it became clear quickly that she still needed space. They shared a bedroom, but each had a study/office of their own. Sometimes she needed to get away from him and the rest of the world. It was there that she laid on the couch, hands folded on her stomach, that she felt a flutter of movement under the few pounds she'd gained. She had furrowed her brow, placed her fingers again on the little mound of flesh, waited. Again, a movement. Not her pulse.
When the doctor greased up her belly when she told of her symptoms, she was confused. He flicked on the machine, and there she saw something unmistakable.
A person. A little person in her. And she felt pretty dumb for not thinking of that first. When she called Will and broke the news, he cried and made reservations at some French place to celebrate.
Months later, she was covered in sweat and her hair was a mess and she was stuck in a tiny little room that was mostly bare. And she looked at the baby in her arms and she cried too. They were happy tears, hormone tears, important, special occasion tears.
In the years that followed, she watched Henry grow. She saw him take his first step, listened to his second word from Michigan over the phone. She finally found someone she wanted to spend every single moment of every single day with, someone to help and hold and nurture. Now, alone was second best.