Hurt sis

I’ve spent most of my life supporting and caring for others, but now I feel like no one does the same for me. It feels like everyone is selfish and only cares about themselves. Sometimes I wonder why I shouldn’t also become selfish or even “bad,” since being good only seems to hurt me. I’m feeling really tired and hurt inside. everyone just do me ,me me me me everytime dont gives a f about how i m doingi just noticed how none check on me like i do to others.its not about Exectations its about feeling of betrayal and hurt that none cares for me. i never get any messages or calls from people i never had friends people always took me for granted for example my cousin when he was in depression i was there for him n supported him throughout like a real sister but when he healed now he dont even talk to me all this hurts