Crouch was sent off early on in the game in the Bernabeu which Spurs went on to lose 4-0 leaving any hopes of progressing further in the competition in tatters.
Speaking to The Mirror, Redknapp admitted it would take the England international some time to recover from the disappointment but insisted he attributed no blame to the forward.
“He’s been low and feels he’s let everybody down but without Crouchy we wouldn’t have been there in the first place," explained the Spurs boss.
"It’ll take him a while to get over it but he can’t walk around and want to hang himself, or something.
"He hasn’t murdered someone, has he? He hasn’t killed someone. I mean, what’s he done?”
"He’s made a ricket, the kid. He’s made a mistake, but what can he do?
“I had a chat with him. As I say, he’s a caring sort of fellow, he’s a lovely bloke Crouchy.
“He’s apologised and he was sick about the whole thing.
“But you’ve got to move on from that now otherwise you go home and you just sit in a dark room for the next six years or something.”
Crouch was sent off after picking up two yellow cards and Redknapp says he has spoken to the striker to ask why he made the challenges so early on, explaining: “He doesn’t know. He just lunged and thought he was going to get the ball and realised he didn’t get there in time."
Tottenham currently sit in fifth position in the Premier League and Redknapp admits that if they are to play in the Champions League again next season that they must finish above Manchester City.
“They [Manchester City] have spent something like £170 million to get in that top four this year," he added.
“City are going well, maybe they could finish second but personally I think our best chance of finishing fourth is finishing above them.
“I’ve loved the Champions League experience and I want more of that on a regular basis if we can do it here.
“It’s hard to do. Arsenal, Chelsea, Man United are not suddenly about to drop out and nor are Man City with the money they have spent.
“Liverpool are going to be up there again. It’s difficult but we want more if it. The Europa League would be a comedown. Nothing compares to the Champions League. It is different class.”