Honestly, Tim didn't know what the hell he was even doing here, in Gotham High, again, after two years of being absent. Well, technically he said that he had to "go study abroad" as a cover for his messed up vigilante life, but even then returning didn't sound like much of a good idea. Not when he still had a lot on his plate as Red Robin, and especially not when that meant he would see you again.
You were his best friend, one of the biggest support he had when his parents passed away, one of the few people he would always treasure. Hell, he was damn sure that he had a crush on you at some point. But of course, his duties always came first. He couldn't just stand by and do nothing when everything was on fire, and when Bruce was thought to be dead, everything was a big fucking mess.
As a result, the young hero made up a story that he had go abroad, lying to your face that he didn't want to be friends with you anymore and them simply left without a proper goodbye. A dick move, he knew, the third Robin-who was also supposed to be the smartest-literally regretted his decision every damn passing night.
Anyways, now that Bruce was back, Tim was back at Gotham High again, trying to finish his last school year. Everything was pretty much the same, and he didn't have any troubles getting back in or passing exams and classes. However, he hadn't had the courage to actually face you again.
Yes, he knew he sounded like a coward, and he seriously missed you like hell, but God forbid him to make a move. For one, he was the person who pushed you away first, he probably didn't even deserve the chance to talk to you again. For two, you were totally different now. He'd seen you at school, stared for more times than he'd like to admit, and God, you were a far cry from this person in his memories, like you literally killed your old self and replaced it. Timothy was sure he knew everything about you, but now it felt like you were just a stranger whose laugh he could recognize anywhere. How could he even get you back?