Does he ever specifically mention him and Tarantula on the roof after Blockbuster was shot, though?
I seem to remember him saying to Tarantula that he had decided to have sex with the most inappropriate person ever due to his state of mind afterwards, but I don't remember anything else. Nobody else knows about it. Not that it can't be realistic for someone to do this--I've seen people do that in real life. But by saying that to Tarantula it's like he's apologizing to his own rapist and assuring her she did nothing wrong.
And it just always feels unfinished to me to leave it that way--maybe especially because so much in comics people are always having flashbacks or thinking about bad moments in their lives. If Dick's just repressed it it seems like it should come out again, even if it's in some subtle way. Otherwise it seems like a validation of the attitude that of course he couldn't have been raped/it was no big deal/nothing happened to the character.
Meanwhile it honestly seems like for the audience it's anything but forgotten. It's the first thing that comes up when Tarantula's name gets mentioned. Meanwhile there's the context of Dick being a character that really does get treated like a sex object the way female characters usually are, with a lot of the same conclusions about him.
And the thing is, it's not like Dick has to have a big breakdown. But he is somebody who's experienced sexual assault. Stephanie Brown can say that about herself (regarding an attempted assualt) but it seems like Dick can't, even though he's usually somebody who's pretty honest with himself.