Ok so It should be understood that “after x attacks you” and “after x attacks and damages you” to be the…

“After X attacks and damages you” checks if the attacked player’s identity was damaged as a result of the attack. Because Green Goblin’s overkill attack did damage your identity, his Forced Response resolves. If your identity did not take damage, his Forced Response does not resolve. The “you” in this ability does refer to your identity.

“After X attacks you” is different in that it only checks if the attack was made and not canceled (e.g. by a stunned status card), in which case the attacked player resolves the ability. The “you” in this ability refers to you the player, so it falls into that exception to the standard “you” rule.