I am an outsider?

Sometimes, I really feel like an outsider. Every single time you are sad or emoing about something, you will never tell me. When I found out, I am always the last one to know. I dun understand why is that if I am important to you, you won't let me know when you are sad. Is not just once or twice, but almost every single time I have to find out about it by myself. If you just dun want me to worried, then let me know whenever you are sad so that I can worry about you for a moment instead of all the time, not knowing when you will need someone to talk to. Being someone so close to you, yet being the person who is the last to know that you are not okay. This feeling Suck to the max.