Getting over things from the past.. (toxicity in my relationship)

I have written in this forum before and I felt like it really helped. In the past year, on a couple of occasions, my boyfriend used to get kind of pouty/frustrated when I didn't want to have sex. Not when I said flat out no, but when I wasn't sure and we started being intimate then I didn't want to anymore. He mostly just seemed distant and pouty for a few minutes than would be fine. More recently, I really tried to explain to him why it wasn't nice and how it made me feel and basically said it needed to change or else I would have to walk away. Since then (and like every problem we've ever had in our relationship) he has changed his behaviour and it hasn't been a problem since. One thing he's really good at is once I tell him something is a no-go, he does actually stop the behaviour. What the problem now is though is for some reason I still can't get over it? that he acted that way in the first place? I have just heard horror stories of how much of a red flag it is and to run. I guess I just would want an outsiders opinion on this topic, and if they believe it's still ok to be with him despite the toxic spout in our past.