Raven had always taken solace in reading.
Even as a child on Azarath, when the monks' lectures became too boring or the judgmental whispers of citizens became too loud for her to ignore Raven often curled into her own world of literature. Her taste for books has expanded since coming to Earth; on Azarath all they had were spellbooks full of archaic symbols and while they did their due in instructing young magi like herself they certainly weren't what she - or anyone - would call leisure reading. Earth however, had a literary canon that reached back centuries, and the prospect of new material elated Raven in a way that she of course couldn't very well express.
The one drawback of human literature is that it played to the emotions much more than any spellbook. Indeed, on Earth that was one of the marks of a great writer and thus great book- making the reader feel. Raven had been trained since childhood to ignore any and all type of emotion, a safeguard against her father and demonic powers that was understood by Raven herself to be practical at the time. However, as Raven read more and more on Earth she came to understand a few things about emotions; and more specifically- her emotions. Emotions, for all accounts and purposes, were not all bad. It was a very human thing, that Raven could let herself experience for a limited time. Of course, she had to set limits. If something pushed her to tears or anger she would have to stop and meditate; lest everything in a five mile radius crash inexplicably forty feet to the left. But it was almost like a guilty pleasure. A small smile for Athena's wit, a blush or eyeroll dedicated to Romeo's pleas to Juliet, and maybe even a gasp because really- is that how it ends?
Raven thought it safe in these times to let her emotions show, and as time went on it wasn't always the story that held her attention. Every kind and supportive female character was Starfire, the well-meaning comic relief was Beast Boy, the protective older brother figure was Cyborg, and every knight in shinning armor was Robin. She might not have been able to express to her friends how much she truly loved them; but when she read every story was theirs and every feeling was shared.
After Trigon, things changed. It wasn't immediate of course, Raven couldn't forget a life of training in a week, but slowly she became more emotive. She would smile at Beast Boy's lame puns, she would quietly sing Disney songs with Starfire, and she would often help Cyborg with the T-car. Her happiness grew, and everyone could see it. The only problem with this new development was that accompanying happiness was of course all her other feelings. Raven came to see that her relationship and thus feelings for Robin stretched farther than she could justify as friendship. As this realization manifested so did jealousy, sadness, and worry. Every small smile he sent some random fangirl on the side of the street made her heart sick, and that made her angry. He wasn't hers, so why should she care? She cared because Raven loved Robin, not like she loved the rest of the Titans, or even Malchior. That made her very, very scared.
Her books never hinted that feeling things all the time would be so hard. They never mentioned the downside and pure intensity emotions could and would bring. Curling back into herself seemed like the only safe option, to live as she did before. So, Raven stopped going with her friends so much, she meditated every day again, and she paid special attention to minimize her contact with Robin.
She never considered that Robin would notice.