Realising I'm all alone[L]

I dont really know where to post this but I need someone to talk to. Recently I gained the courage to ask a girl out by writing her a song. The song wasn't the best but it was funny and she rejected me. I mean she didn't reject me directly but I sensed it and now I won't see her for the next 3 months because of the school break. So that situation made me realise that I will be alone forever and will never be able to get a girlfriend. I know this sounds like some stupid teenager drama because I am a teen but still it has made me super depressed and suicadal. The only thing I could do is ask her to go out on a date by messages but I feel like if she rejects me it will be very awkward in class. So if anyone can help me I would be very grateful.