Disclaimer: I don't own Rizzoli and Isles and never will. No copyright infringement intended.
Maura knows that Jane isn't in love with her. She doesn't expect her best friend to return her feelings. She's sort of okay with that. Maura's had a long time to get used to being in love with Jane.
"What are you thinking about?" Jane asks Maura. She's worried about her. Maura's been really quiet lately and won't tell her why.
"This autopsy I just did. It was really interesting," Maura lies. She smiles and goes back to watching TV. She'll be fine.
Jane is in love with Maura, but she's never going to say a word. She wants to keep their friendship as is. If she tells Maura, she's going to lose her. She's been afraid of rejection for years, and that's why this is going to remain a secret.
"Our latest case was pretty interesting," she says to Maura. Talking about the job is easier than thinking about her feelings for Maura. She'll pretend that everything is okay.
It's overdramatic, but Maura feels like she's dying inside from keeping this secret from Jane. It hurts so bad, and there's nothing she can do about it.
Maura and Jane will never tell each other their secret, and they don't know it's going to solve all their problems.
And that's the saddest thing about the entire situation. Nothing between them will change as long as Maura and Jane keep lying.