#returns

This really isn't a fic request but I think there's more to Dick leaving that just Bruce's parenting attempt when he Dick got shot by Joker not long after recovering from the attack by Harvey.

Not only do we very obviously have the issue of Bruce and Dick's relationship straddling the lines between siblings, vigilante partners, and parent/child. So the attempt at suddenly being a solidly parental abd authoritative figure probably kicked off the extremity of Dick's reaction.

We have Dick holding onto Robin as his last connection to his parents. Having Bruce try to take away Robin probably didn't go over too well.

Anyway

So, we've seen in comics how much the vigilante life consumes a person's social, support and time. It's very difficult for vigilantes to maintain strong relationships outside of vigilante and vigilante adjacent circles.

Part of Dick's reaction has to be the absolute terror at losing access to all of his best friends and mentors. At least subconsciously he had to realize that they probably wouldn't have time to hang out with him or interact with him as a civilian.

Him almost immediately hard latching onto the titans supports this pretty well.

Actually, this neatly explains the emotional attachments we see to the vigilante identities of a lot of characters. Because it's so much more than an identity or a job. It's basically your entire social circle that you risk losing if you're no longer a mask.