My kids didn't meet anyone new in my life before six months.
I tell ya -
I agree with your ex.
Parading a bunch of potential 'new parents' in front of children is a horrible thing to do to them. They get attached, then it doesn't work out .... it's divorce time all over again. And as a parent, our job (hiopefully is to STOP the passing down of the cycle of involving with A's or otherwise unhealthy personages.
I've seen it and seen it and it is NEVER pleasant. It's NEVER a 'mutual agreed' parting.
Not with a kid.
Even with a teenager. ESPECIALLY with a teenager.
my own grandaughter is having to cope with her step father
moving out and her own mother dating and bringing home men.
Even for dinner is an upset.
I just never could see any benefit from that.
My advice is to keep the two separate.