I'm thinking of there being no one who can help me out.
Why do you think there is no one who can help you?
I see that no one cares about me and everyone leaves me alone
It is understandable to feel alone and that there is nobody out there for us but it is not good to keep those feelings inside. It is better to seek help and make your life better.
I wouldn't know how to keep my feelings inside.
You should talk to someone you trust with these feelings.