alone and lonely are different

i feel lonely inside a crowd room while there are 1000 people standing and talking to each other. I feel like i'm nobody's child and i'm lost.

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i feel lonely when i go to my rest room, i lock the door, then i sit on the floor, i put my headphone in my ears with any genre of song, i close my eyes, and imagine there's someone besides me. Even sometimes tears come down easily.
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i am lying in my bed alone in my room, no one inside my room except me, i'm thinking of someone, i am smiling, i feel happy, a world seems to be mine, and everything i do makes me know how important i am.

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i was alone in my house with nobody inside it. I felt like "this house is empty and too big for only 1 person like me". Nothing i could do here. I just wanted to go outside with lots of people. I hate being alone and ignored by others.

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can you see the differences between those paragraphs? even you can feel lonely inside the crowd room, and you can feel happy while you're alone. People might not know what your feeling is, but if your feel worse while you are hanging out with groups of people that u are not close with , ask yourself why, and what is the advantages and disadvantages of being lonely in the middle of the crowd. i think, the advantages are: we know that we are not comfortable with them, try to openmind and let yourself to adapt first. It takes time and time will answer.