Thinking about ex while in a relationship?

I need advice but please keep your judging to yourself

Me and my ex broke up almost 5 months ago we were toxic we started dating a year ago we were in situationship for like 2 month and stopped then after a year we got together but we only lasted for like 3 months and maturely break up

We are not friends but we talk when we see eachother

2 month after we broke up I got with my current boyfriend we have been together 2 months now I love him and he treats me so well unlike my ex he cares about me

But for some reason I can't stop thinking about my ex it's not like I still love him but every time I do something with my boyfriend I think about my ex or when I do something for my boyfriend I never did for my ex it makes me sad

I even called my boyfriend by my ex's name once and he was mad and asked me if I'm still in love with my ex

I don't know why I still think about him even though we both hurted eachother I was not even happy in the relationship

So please I know it's wrong but help me out

Thinking about ex while in a relationship?
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