OP.
My son has a 'crazy ex girlfriend'. Genuinely.
He supported her as best he could but, in the end, she had a psychotic breakdown and was hospitalised. He broke up with her after a lot of wrangling with himself because, after some of the things she said and did, the relationship was damaged beyond repair.
That was 12 months ago. They were together for 18 months. He isn't even considering dating anyone else yet because he needs to look after himself after what was a traumatic period for both of them.
The only people who know are me, a couple of close friends he confided with at the time and a couple of mutual friends who witnessed some of her behaviours (generally and towards him).
He has already said that he won't date until he feels ready to after the experience and will never tell any future girlfriend about her - she was ill; he respects her and he did love her at the time.
That is how someone with a genuinely 'crazy' ex behaves. They don't go straight into a new relationship dumping all their dirty laundry on a new person; nor do they run down someone who was ill; nor do they bond with someone on the basis of a shared shit relationship experience.
I wonder what of your quirks and behaviours will be redefined as 'crazy' in the future when he wants to use it to his advantage?
I would be very wary of him.
Men with 'crazy' exes who are happy to run said exes down are quite often the cause of said craziness.
No mature, worth having man has a baby with someone because she threatens to dump him otherwise. And I bet he loved the bikini in the snow quirkiness of her when they were together.