People make time for who they want to make time for. People text and reply to people they want to talk to. Never believe anyone who says they've been too busy. If they wanted to be around you, they would.
"Hargailah satu sama lain, karena suatu hari nanti kalian akan berpisah secara tiba-tiba dan tanpa peringatan."
Sayyidina Ali bin Abi Thalib
Khalifah Keempat Kekhalifahan Rasyidin
People close to you get mad easily because you are a safe space. You always there and they may take your presence for granted and stop putting effort to be polite or manage their moods. As a close confidant, the expect you to know better or read their mind.