Harley Quinn and the Joker

I admit, I don't have as much DC experience compared with Marvel. I watched Batman: the Animated series but I only remember that Harley Quinn was weird.

Now everyone seems to hold up Harley Quinn and the Joker as one of these awesome couples of all time. Everything I've seen of the Joker, apart from the recent video game ending, makes him appear to be a psychopath.

To me, my assumption about Harley Quinn and the Joker would be a one-sided romance where she's putting way more into it than getting back. On paper, it sounds way worse than the typical Beauty and the Beast tale that everyone complains spreads archaic, dangerous ideas about relationships.

I know Harley Quinn can hold her own but still...am I wrong? Is this an awesome, healthy relationship that I should get on board with?