Sorry, but untill you have experienced suicidal thoughts yourself you have no idea how hellish it can be for someone. How dare you accuse the OP of being selfish, you have no idea what you are talking about! If the OP decides not to take the overdose, it shouldn't be because he/she is worried about the remaining friends and family, instead it should be because he/she has realised that there is hope for a better future and that they should not give up. Even if the future doesn't seem bright and doesn't turn out that way, I still think that suicide is not the way to go, giving up is letting yourself fail. Give yourself a chance OP.
Personally what helps me is to have faith that God will bring me through. He gives me strength.