To be jealous of boyfriend's history with his ex?

[Retrojealousy]

My boyfriend was with his ex wife for a very long time and they have kids together, we have been together a year and a half, not even close to the amount of time they were together. They are divorced now, but I still feel jealous of the long history they have together and I also know it wasn't his decision to end things which makes me feel more insecure.
Is this normal to feel like this? Do you ever feel jealous of your partner's past relationships?

I would suggest gently that this relationship isn’t for you if his past is eating you up, as it’s something he literally can do nothing about.

Ha! I could have written this. It has eased over time and definitely improved after we got married. I also worked on myself a lot - I was surprised at the jealousy I felt.

How old are you? Did you come to the relationship with no history?

I think this is maybe about insecurity or something on your part, maybe something to get help with, x