Some people want to die because they don't know how to live their life, other people want to keep their life because they've learned the true value of being alive. Pain can be a lesson that makes you see the importance what's worth living, happiness is an experience that can last while you're breathing. I don't know how true it is, but I had those thoughts when I was still a suicidal child caught in a prison of isolation born of my experience and mind. Then came college I learned to befriend other people and realized life doesn't have to be so lonely after all. Despite all the pain this world can possibly place on your shoulders it's not that impossible to carry when you have other people helping you through...
There are a lot of people who will make you feel like you are the most worthless person on the face of the universe but that doesn't mean that they are right. You have to develop enough sense and dignity to stand up for yourself when you know you're right. Getting bullied rarely happened to me back in the day, partly because of my size. Who'd want to pick on someone who could easily crush you with the sheer weight of their stomach. Something that brought me to the topic of obesity but anyway.
Here are probably some things you may want to consider in building up dignity.
1. Have good family relationships.
Aside from close friends what could be more comfortable than having your family around to cheer you up when you're feeling gloomy and pick you up when you're face is deep down on the ground? you shouldn't be scared to tell your parents when you have problems and you should know how to trust them, after all they're your parents.
2. Have good friendships.
Avoid making friends with people who indulge you into vices. It's alright to make friends with people who have Vices but advise you not to copy them. There are people who know when they're wrong and don't want you to follow. make good friends and do what you can to keep your relationships good, that way, even in the absence of good family ties, you'll still have a shoulder to cry on when you need it the most.
3. You may want to try learning self defense.
I'm not a fan of Martial arts but I do like being able to defend myself from someone who stretches out their hand and asks you for your lunch money. Unless the person has a really bad weapon or a crazed mental state, I don't think I'd give in easily if I knew self defense. Find the nearest Taijutsu school quick!
4. Build up a good personality.
By good I don't mean too good. You have to know when people are being genuinely good to you or not, if all you do is say "Yes" and you don't know how to say "No" you may just be getting yourself into a deep hole. Who wouldn't like a nice person with a good personality? Well, some people are just too hard to please.
5. Have faith in yourself.
Making mistakes is just a part of being human, you shouldn't be scared to commit mistakes but avoid them as much as possible and be scared when you stop making mistakes, you may just have evolved into something else @_@ or not. when you feel everybody else is trying to get you down, you should learn how to pick yourself up and recover.