Everybody feels worthless at one point of time, I have, she has, he did. Even the one whom you think has a perfect life has her own blues to deal with. Happiness is something you create not something you go after. The best way is to be content with who you are, what you have, who you have. Here are a few ways that could actually help you to.
1. Accept yourself:
First learn to deal with your insecurities, know that this is how people actually keep making you think of yourself lowly. So make peace with it. You should realize that you are wonderfully and fearfully made. Know that you are an unique piece of art, your flaws are what defines you don't let people look down on you because of them, remember how beautifully the wild flower grows from the places you thought were dead. You are that wild flower that can make it through whatever you are going through.
You feel sad when you don't have what your friend has, what is trending, what is fashionable but know that not everything you want is your need. Once you learn to differentiate it you will make you more satisfied with your life, with yourself. Invest in your needs and don't let people rule your life. Remember it is your life, you do what you want to not because someone else thinks you should.
Know, not every happy face you see in your Instagram page has that awesome life. You know that it feeds you with lies with edited version of happiness. Even you might be guilty of it but deep down you know all you are doing is living in the make belief world of your own. So try to love, to live the moment that you cannot frame it. Don't waste you potentials by comparing it with the beautiful lies of others.
Stop letting someone validate your reason of happiness, your reason of existence. Stop putting so much efforts on others. Invest in yourself. You will be there for yourself when everybody leaves.
You stay, even if to just bare the pain but you stay. So take time and love yourself, you will be the best friend you will ever need.
People may be unhappy with what they are going through right now, may be dealing with similar to death like experience emotionally or physically. But be content that this is just a phase, good or bad it will pass and one fine day every trouble you went through will make sense, and things will fall into place.