There are things I did a lot when I was younger, and I look back on them now and roll my eyes at how juvenile I was—but the reason I stopped doing them was simply because I aged and my priorities changed.
I'd characterize that as internal conflict, however. I think the process of growing up and maturing, which we all go through as we transition from children to adults, is impacted by both internal and external conflicts, many of which are quite compelling (which is why coming of age stories are so popular).