AIO? My boyfriend still talks to his ex

My boyfriend still talks to his ex girlfriend. They dated for 6 years and broke up when he proposed to her and she declined.

When we first started dating he made it seem like business only - they had taken out a loan together and he paid it off. Then he had a few of her things and he needed to see what she wanted to keep or toss She's married and pregnant now, sends ultrasound photos and calls him when her husband upsets her. I asked one time if he would stop talking to her if I asked him to, and he said "well you don't control my life" and we moved on from that quickly.

He just told me the baby name she picked. It was on my list also he insists we could still pick it but I completely disagree. I'm considering telling him to cut her off or I'll leave him, am I overacting or is this normal?