I worry about my kids too. I’ve always expected them to do better than their best and now, in their early twenties, both are successful. However, life’s little defeats hit them hard.
I went through a period where I was depressed but powered through it by taking a “fuck the world” attitude. I never want them to experience what I did.
I wonder now if demanding excellence from them at such a young age set them up for depression later on. But, so far they seem happy and content.
Please don't think that you pushing them to do their best will lead to depression later. No one knows when or if depression will strike. And certainly no one knows why.