How do guys come off as desperate

Let me break this down for you kid

Me expressing my affection for a girl and not having it reciprocated.
No woman is obligated to reciprocate. No woman owes you anything and not every woman is going to be interested in you.

I've had about 8 times when I asked a girl out and got turned down...with the the one that really broke me being the same girl in 3 different very romantic (but subtle) ways...I've tried to move on, even asked out a different girl
If you are desperate and always looking for a girl to be with then these girls know that you don't give a shit about who you're asking out as long as someone says yes. Desperation is incredibly unattractive because it shows a complete lack of standards. I turned down more than one guy like you in high school because they would ask out so many girls that it was obvious that I was nothing special to them. There was no connection, but for some reason they thought that because we would chat regularly or because I was so friendly that they should be able to bag me up and have me. Besides, you're in high school, why are you so desperate for a relationship?

To add on to this I'm depressed, don't have any emotional outlet
If you are depressed you need to start by building solid friendships. Get over the idea that getting a girlfriend will fix everything and give you a reason to be happy because it won't. Your goal needs to be finding people who will build you up and make you feel good about yourself, finding people you can talk to about what's going on with you, and getting some therapy to help you to learn to appreciate yourself and give you ways to cope with the depressed feeling.

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