I'm sure most of us have been there before. You fall in love with this special someone and after asking them out you end up being disappointed, hurt and possibly even believe that you are not worthy of love because they told you they dont feel the same way as you do for them and dont see you as more than a friend.
In order to reduce the pain, stress and depression that such a situation brings i have some tips that will hopefully help you in some way if you find yourself in a situation like this.
Stop making them the only thing that matters in your life.
Being rejected and hurt sucks and its a situation no one wants to be in, we can all agree on that.
But always being there for someone who basically treats you like shit and doesn't appreciate you isn't going to make such a situation any better.
That's why you should stop making them the only priority in your life and stop treating them as if they are the pope or Jesus himself. Just like every other human being, this person too has flaws. Instead, learn to value yourself and your time better and do things that contribute to your well being and self-improvement. You can for example start learning to eradicate negative thought patterns, working out, do meditation, hang out with friends/family or actively practice a hobby like making music, cooking and so on.
Don't ignore your feelings. Embrace them and let them go.
As a man i grew up with the believe that all men always have to be strong and are not allowed to show any kind of sensitive emotions. This is complete bullshit. While it is true that you shouldn't be a wimp that starts crying for every little thing, trying to suppress your feelings of sadness, grief etc. will not only make your depression worse but it also isn't going to make them disappear. It will only temporarily make you feel better but sooner or later those feelings and the ruminating will return and hold you back when instead you could have let them go some time ago and done better things that contribute to your well being. So if you dont want to be alone ask a friend or someone else who is close to you and talk with them about it.
Realize that recovery always takes time.
You probably won't feel better in one day, a week or a few months. It's different from person to person how long it takes to fully process the feelings and let go. So have patience and give it time.
Distance yourself from them.
Similar to the first point, don't make the person that dumped you your highest priority in life. Get rid of things that remind you of them. Don't stalk or cyberstalk them and don't immediately give them a response if they reach out to you. If you have to work with this person or see them at school every day i suggest treating them like a regular colleague. Say hi if they greet you but leave it at that.
Know that you are worthy.
It's easy to start believing you are not good enough when in a situation like this. You might not have met this persons preferences and there probably wasn't any physical attraction (which is likely the number one reason he/she rejected/friendzoned you) but this doesn't mean you are unworthy of respect, affection, love and companionship. It's impossible for anyone to always meet other peoples preferences and expectations.
Stay away from internet guides that cost money which supposedly show you how to get out of the friend zone.
There are many websites which claim to have guidebooks/ebooks etc. that show you "how to win her back" or "how to get out of the friend zone". While there are some genuine tips that really work and help out there, websites like i mentioned i believe are just scams run by people who recklessly use the vulnerability of other people to make money.
It is totally up to you if you want to pay for something like this but im sure those "guides" are complete bullshit and won't get you where you want to be, even if they claim otherwise.
Plus i believe there are no guides for life since everyones situation is unique with a lot of differing aspects.
And last but not least, stay positive.
I know it's hard to think positive in a situation like this. But ruminating and only focusing on the negatives isn't going to make it better. Stay positive and accept that life is not always a piece of cake.
So that's it. Hope is of some help for you