How do I avoid getting hurt by the little things?

I know it’s valid for me to get upset over something if it genuinely upsets me, but it gets to a point. I know that sometimes I get upset over the stupidest of things. For instance, my friend won’t like my posts despite liking everyone else’s. It makes me want to cry because it feels like something is wrong with me. But that feels stupid to me, so how do I avoid getting hurt by little things?