Look, when someone you are seeing is talking about their crazy ex, you are probably supposed to say somewhat supportive things. You are supposed to tell them that they are not actually any of the horrible things that she is saying. That’s really all they want.
Unless you are Betty Draper, in which case you should just stand there, silent with a cigarette. You are so glamorous it blows my mind.
If you are not Betty Draper, tell your boyfriend he’s good at badminton. People like hearing that.
Look, taking into account this woman may not be “crazy” we all have friends who have gone somewhat irrational after a break-up. You haven’t said “you’re being crazy.” You’ve said “you’re in pain, take all the time you need. When you boiled his bunny that was just you expressing your feelings.” No, we haven’t said that. But we have let people dump expired dairy products all over the place in fits of rage (you’d be astonished by the number of expired dairy products in my apartment). Anyhow, remember that this girl is someone you would probably sympathize with if circumstances were reversed. Maybe you’ve even been this girl.
Send her a small drawing of a dinosaur and 5 tubs of expired yogurt with a note that they are “for throwing at people like a T-Rex.” That makes people happy. That’s what you’d do with a friend.
Your ex can, but he still had a relationship with her. You can’t say she’s crazy. It’s like talking about how you hate your drunken aunt, but realizing you’d be horribly insulted if anyone else did that.
If she is someone you sort of know, it’s going to be tempting to say “hey, so, what happened between you and Beelzebub (your boyfriend’s name is weird, by the way).” Don’t do this.